Coformulation of an oil-soluble herbicide and a water-soluble herbicide

ABSTRACT

A stable, liquid concentrate herbicidal composition is provided. The composition comprises a water-soluble herbicide in a continuous aqueous phase and an oil-soluble herbicide in a discontinuous oil phase.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional ApplicationSerial No. 60/269,193 filed Feb. 15, 2001 and U.S. ProvisionalApplication Serial No. 60/331,348 filed Feb. 14, 2001 and is acontinuation-in-part of U.S. patent application Ser. No. 09/633,193filed Aug. 4, 2000, now U.S. Pat. No. 6,369,001, which claims priorityfrom U.S. Provisional Application Serial No. 60/148,423 filed Aug. 11,1999.

FIELD OF THE INVENTION

The present invention relates to compositions useful in agriculturecomprising at least two herbicidal active ingredients, one of which isan oil-soluble herbicide and the other of which is a water-solubleherbicide. More particularly, the present invention relates to stableliquid concentrate compositions of such herbicidal active ingredients.

BACKGROUND OF THE INVENTION

As a means of killing or otherwise controlling unwanted plants, e.g.,weeds, in agriculture and related endeavors, it is desirable to treatsuch plants or the locus thereof with chemical herbicides. A commonmethod of herbicidal treatment in agricultural endeavors is to treat afield to remove or control unwanted vegetation as preparation forplanting a crop plant, a method otherwise known as “burndown.” However,single herbicides typically lack the weed control spectrum, e.g., therange of weed species effectively controlled by the herbicide, to fullycontrol the diversity of weeds in a field. Therefore, it is common toapply two or more herbicides simultaneously in order to achieve thedesired spectrum of control. To facilitate the simultaneous applicationof two or more herbicides, it is common to package the differentherbicides separately as concentrate formulations, which can be admixedwith water in a spray tank by the end user, a method also known astank-mixing. More conveniently, however, the different herbicides can becoformulated in a single concentrate formulation, requiring onlydilution in water by the end user prior to application by spraying. Sucha formulation is often known as a package-mix.

Further, applying combinations of two or more herbicides simultaneouslyto a field may be necessary or desired for synergistic effects otherthan an increased control spectrum. For example, many water-solubleherbicides such as N-(phosphonomethyl)glycine have prolonged visualsymptomology, that is, it takes a relatively long period of time (i.e.,up to two weeks or more) for susceptible plants to show the visualeffects of treatment. Generally, such extended periods without anyvisual indication of herbicidal effectiveness detracts from thecommercial value of a herbicidal product. Therefore, it is oftenbeneficial to combine two or more herbicides in a tank mix or apackage-mix that will provide for more rapid burndown and earlier visualsymptomology, thus improving the value of the overall herbicidalproduct.

Package-mix formulations present numerous challenges to the formulatorof agricultural chemicals such as herbicides. For example, theformulation should contain the herbicidal active ingredients at as higha total concentration as possible, for maximum convenience to the enduser and to minimize packaging and shipping costs, while keeping theactive ingredients within the desired weight ratios with respect to eachother. Most importantly, the package-mix formulation must exhibitsufficient physical and chemical stability to have an effective shelflife of at least a few months, preferably at least a year, and ideallyat least two years.

Where the package-mix formulation contains a first herbicide that isoil-soluble and that undergoes chemical degradation, even at a slowrate, in water, and a second herbicide that is water-soluble, thechallenge of providing a storage-stable liquid concentrate formulationis particularly acute. Water used as the solvent for the secondherbicide acts as a degradation medium for the first herbicide.Typically, hydrolysis is the most common water-mediated degradationmechanism; however, package-mix formulations with chemically unstableactive ingredients are also subject to oxidation, dehalogenation, bondcleavage, Beckmann rearrangement and other forms of degradation.

Liquid concentrate coformulations of two herbicidal active ingredients,one of which is water-soluble and the other of which is oil-soluble, areknown in the art in the form of emulsions, most commonly oil-in-watertype emulsions having a discontinuous oil phase dispersed in acontinuous aqueous phase with the aid of one or more emulsifying agents.The water-soluble active ingredient is contained predominantly in theaqueous phase and the oil-soluble active ingredient is containedpredominantly in the oil phase. The individual oil particles can belarge enough to interfere with the transmission of light, giving rise toa cloudy or milky emulsion known as a macroemulsion. However, where theindividual oil particles are so small as to allow light to betransmitted without noticeable scattering, the emulsion is clear, i.e.,transparent, and is known as a microemulsion. Microemulsions offer anumber of practical advantages, one of the most important being thatthey typically remain homogeneous without agitation for long periods oftime. In this respect, a microemulsion formulation can be handled by anagricultural technician or other user with the same ease and convenienceas a simple aqueous solution. However, selecting excipient ingredientsfor the preparation of a microemulsion is not necessarilystraightforward or easy.

Difficulties in preparing stable microemulsions suitable for effectiveweed control and good crop safety are compounded when the activeingredients to be coformulated are a water-soluble herbicide and anoil-soluble herbicide. For example, one challenge is that water-mediatedchemical degradation, e.g., hydrolysis, of the oil-soluble herbicidemust be minimized. Minimizing hydrolysis is especially difficult inmicroemulsions, where the oil particles containing the oil-solubleherbicidal active are extremely small and therefore present a very largeinterfacial area with the aqueous phase.

Another challenge is that microemulsions must contain surfactants, whichtend to facilitate transfer of the oil-soluble herbicidal active acrossthe large interface between the oil and aqueous phases, increasing thepotential for chemical degradation. However, surfactants are importantto the microemulsion composition, functioning as emulsifying agents tophysically stabilize the microemulsion, as dispersants to preventaggregation of oil particles when the microemulsion is diluted in waterfor application to plants, and as adjuvants to enhance herbicidalefficacy of one or both active ingredients, for example by improvingretention on or adhesion to foliar surfaces of the applied compositionor by improving penetration of the active ingredient(s) into or throughthe cuticles of the plant foliage.

SUMMARY OF THE INVENTION

Among the several features of the invention, therefore, may be noted theprovision of a novel liquid concentrate herbicidal composition useful inagriculture wherein at least two herbicidal active ingredients, one ofwhich is a water-soluble herbicide and the other of which is anoil-soluble herbicide, can be coformulated; the provision of such anovel composition comprising a continuous aqueous phase having adiscontinuous oil phase dispersed therein; the provision of such a novelcomposition having a broader weed control spectrum; the provision ofsuch a novel composition that exhibits rapid burndown and early visualsymptomology; the provision of such a novel composition that allows forhigher loading of herbicidal active ingredients; and the provision ofsuch a novel composition which has prolonged storage stability and isrelatively easy to use.

Briefly, therefore, the present invention is directed to a liquidconcentrate herbicidal emulsion composition comprising a water-solubleherbicide in water and an oil-soluble herbicide. The water-solubleherbicide and the oil-soluble herbicide are independently present in aconcentration that is biologically effective when the composition isdiluted in a suitable volume of water and applied to the foliage of asusceptible plant. The composition further comprises a stabilizingamount of one or more water-soluble chlorides selected from hydrochloricacid, alkali metal chlorides, ammonium chloride, low molecular weightorganic ammonium chlorides and quaternary ammonium chloride surfactantssufficient to inhibit substantial degradation of the oil-solubleherbicide; and one or more surfactants present in a concentrationsufficient to provide acceptable physical stability of the emulsion andprovide acceptable dispersion of the emulsion upon dilution thereof in asuitable volume of water for application to plants. The composition isfurther characterized in that the oil-soluble herbicide is selected fromthe group consisting of acetochlor, alachlor, ametryn, amidosulfuron,anilofos, atrazine, azafenidin, azimsulfuron, benfluralin, benfuresate,bensulfuron-methyl, bensulide, benzfendizone, benzofenap, bromobutide,bromofenoxim, butachlor, butafenacil, butamifos, butralin, butylate,cafenstrole, carbetamide, chlorbromuron, chloridazon, chlorimuron-ethyl,chlorotoluron, chlorpropham, chlorsulfuron, chlorthal-dimethyl,chlorthiamid, cinidon-ethyl, cinmethylin, cinosulfuron, clomazone,clomeprop, cloransulam-methyl, cyanazine, cycloate, cyclosulfamuron,daimuron, desmedipham, desmetryn, dichlobenil, diflufenican, dimefuron,dimepiperate, dimethachlor, dimethametryn, dimethenamid, dinitramine,dinoterb, diphenamid, dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanofan, isoproturon, isouron, isoxaben,isoxaflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulfuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanil, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenylchlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.

The present invention is further directed to a liquid concentrateherbicidal emulsion composition comprising a water-soluble herbicide inwater and an oil-soluble herbicide. The water-soluble herbicide and theoil-soluble herbicide are independently present in a concentration thatis biologically effective when the composition is diluted in a suitablevolume of water and applied to the foliage of a susceptible plant. Thecomposition further comprises a substantially water-immiscible organicsolvent; at least one emulsifying agent having a tertiary aminefunctionality; and a stabilizing amount of one or more water-solublechlorides selected from hydrochloric acid, alkali metal chlorides,ammonium chloride, low molecular weight organic ammonium chlorides andquaternary ammonium chloride surfactants sufficient to inhibitsubstantial degradation of the oil-soluble herbicide. The composition isfurther characterized in that the oil-soluble herbicide is selected fromthe group consisting of acetochlor, alachlor, ametryn, amidosulfuron,anilofos, atrazine, azafenidin, azimsulfuron, benfluralin, benfuresate,bensulfuron-methyl, bensulide, benzfendizone, benzofenap, bromobutide,bromofenoxim, butachlor, butafenacil, butamifos, butralin, butylate,cafenstrole, carbetamide, chlorbromuron, chloridazon, chlorimuron-ethyl,chlorotoluron, chlorpropham, chlorsulfuron, chlorthal-dimethyl,chlorthiamid, cinidon-ethyl, cinmethylin, cinosulfuron, clomazone,clomeprop, cloransulam-methyl, cyanazine, cycloate, cyclosulfamuron,daimuron, desmedipham, desmetryn, dichlobenil, diflufenican, dimefuron,dimepiperate, dimethachlor, dimethametryn, dimethenamid, dinitramine,dinoterb, diphenamid, dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanofan, isoproturon, isouron, isoxaben,isoxaflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulfuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanil, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenylchlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.

The present invention is further directed to a liquid concentrateherbicidal microemulsion composition having a continuous aqueous phaseand a discontinuous oil phase. The composition comprises a water-solubleherbicide in the aqueous phase present in a concentration that isbiologically effective when the composition is diluted in a suitablevolume of water and applied to the foliage of a susceptible plant. Thecomposition further comprises an oil-soluble herbicide in the oil phasepresent in a concentration that is biologically effective when thecomposition is diluted in a suitable volume of water and applied to thefoliage of a susceptible plant; and at least one emulsifying agenthaving a tertiary amine functionality wherein the emulsifying agent ispresent in a concentration sufficient to provide acceptable physicalstability of the microemulsion. The composition is further characterizedin that the oil-soluble herbicide is selected from the group consistingof acetochlor, alachlor, ametryn, amidosulfuron, anilofos, atrazine,azafenidin, azimsulfuron, benfluralin, benfuresate, bensulfuron-methyl,bensulide, benzfendizone, benzofenap, bromobutide, bromofenoxim,butachlor, butafenacil, butamifos, butralin, butylate, cafenstrole,carbetamide, chlorbromuron, chloridazon, chlorimuron-ethyl,chlorotoluron, chlorpropham, chlorsulfuron, chlorthal-dimethyl,chlorthiamid, cinidon-ethyl, cinmethylin, cinosulfuron, clomazone,clomeprop, cloransulam-methyl, cyanazine, cycloate, cyclosulfamuron,daimuron, desmedipham, desmetryn, dichlobenil, diflufenican, dimefuron,dimepiperate, dimethachlor, dimethametryn, dimethenamid, dinitramine,dinoterb, diphenamid, dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanofan, isoproturon, isouron, isoxaben,isoxaflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulfuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanil, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenylchlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.

The present invention is still further directed to a liquid concentrateherbicidal microemulsion composition having a continuous aqueous phaseand a discontinuous oil phase. The composition comprises a water-solubleherbicide in the aqueous phase and an oil-soluble herbicide in the oilphase. The water-soluble herbicide and the oil-soluble herbicide areindependently present in a concentration that is biologically effectivewhen the composition is diluted in a suitable volume of water andapplied to the foliage of a susceptible plant. The composition furthercomprises a stabilizing amount of one or more water-soluble chloridesselected from hydrochloric acid, alkali metal chlorides, ammoniumchloride, low molecular weight organic ammonium chlorides and quaternaryammonium chloride surfactants; and one or more surfactants present in aconcentration sufficient to provide acceptable physical stability of theemulsion and provide acceptable dispersion of the emulsion upon dilutionthereof in a suitable volume of water for application to plants. Thecomposition is further characterized in that the oil-soluble herbicideis selected from the group consisting of acetochlor, alachlor, ametryn,amidosulfuron, anilofos, atrazine, azafenidin, azimsulfuron,benfluralin, benfuresate, bensulfuron-methyl, bensulide, benzfendizone,benzofenap, bromobutide, bromofenoxim, butachlor, butafenacil,butamifos, butralin, butylate, cafenstrole, carbetamide, chlorbromuron,chloridazon, chlorimuron-ethyl, chlorotoluron, chlorpropham,chlorsulfuron, chlorthal-dimethyl, chlorthiamid, cinidon-ethyl,cinmethylin, cinosulfuron, clomazone, clomeprop, cloransulam-methyl,cyanazine, cycloate, cyclosulfamuron, daimuron, desmedipham, desmetryn,dichlobenil, diflufenican, dimefuron, dimepiperate, dimethachlor,dimethametryn, dimethenamid, dinitramine, dinoterb, diphenamid,dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanofan, isoproturon, isouron, isoxaben,isoxaflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulfuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanil, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenylchlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.

Still further, the present invention is directed to a liquid concentrateherbicidal microemulsion composition having a continuous aqueous phaseand a discontinuous oil phase. The composition comprises a water-solubleherbicide in the aqueous phase and an oil-soluble herbicide in the oilphase. The water-soluble herbicide and the oil-soluble herbicide areindependently present in a concentration that is biologically effectivewhen the composition is diluted in a suitable volume of water andapplied to the foliage of a susceptible plant. The composition furthercomprises a substantially water-immiscible organic solvent in the oilphase; at least one emulsifying agent having a tertiary aminefunctionality; a stabilizing agent present in a concentration sufficientto inhibit substantial degradation of the oil-soluble herbicide; and oneor more dispersing agents present in a concentration sufficient toprovide acceptable dispersion of the microemulsion upon dilution thereofin a suitable volume of water for application to plants, but notsufficient to destabilize the microemulsion prior to such dilution. Thecomposition is further characterized in that the organic solvent isselected such that the oil-soluble herbicide has an organicsolvent/water partition coefficient, expressed as a logarithm, of about4 or greater; the emulsifying agent is present in a concentrationsufficient to provide acceptable physical stability of themicroemulsion; and the oil-soluble herbicide is selected from the groupconsisting of acetochlor, alachlor, ametryn, amidosulfuron, anilofos,atrazine, azafenidin, azimsulfuron, benfluralin, benfuresate,bensulfuron-methyl, bensulide, benzfendizone, benzofenap, bromobutide,bromofenoxim, butachlor, butafenacil, butamifos, butralin, butylate,cafenstrole, carbetamide, chlorbromuron, chloridazon, chlorimuron-ethyl,chlorotoluron, chlorpropham, chlorsulfuron, chlorthal-dimethyl,chlorthiamid, cinidon-ethyl, cinmethylin, cinosulfuron, clomazone,clomeprop, cloransulam-methyl, cyanazine, cycloate, cyclosulfamuron,daimuron, desmedipham, desmetryn, dichlobenil, diflufenican, dimefuron,dimepiperate, dimethachlor, dimethametryn, dimethenamid, dinitramine,dinoterb, diphenamid, dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanofan, isoproturon, isouron, isoxaben,isoxaflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulfuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanil, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenylchlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.

Still further, the present invention is directed to a liquid concentrateherbicidal microemulsion composition. The composition comprises acontinuous aqueous phase comprising N-(phosphonomethyl)glycine or a saltthereof and a discontinuous oil phase comprising an oil-solubleprotoporphyrinogen oxidase inhibitor (PPO) herbicide. TheN-(phosphonomethyl)glycine and the PPO herbicide are independentlypresent in a concentration that is biologically effective when thecomposition is diluted in a suitable volume of water and applied to thefoliage of a susceptible plant. The composition further comprises asubstantially water-immiscible organic solvent in the oil phase; atleast one emulsifying agent having a tertiary amine functionality; astabilizing agent present in a concentration sufficient to inhibitsubstantial degradation of the PPO herbicide; and one or more dispersingagents present in a concentration sufficient to provide acceptabledispersion of the microemulsion upon dilution thereof in a suitablevolume of water for application to plants, but not sufficient todestabilize the microemulsion prior to such dilution. The composition isfurther characterized in that the organic solvent is selected such thatthe oil-soluble herbicide has an organic solvent/water partitioncoefficient, expressed as a logarithm, of about 4 or greater; theemulsifying agent is present in a concentration sufficient to provideacceptable physical stability of the microemulsion; and the PPOherbicide is selected from the group consisting of azafenidin,benzfendizone, butafenacil, cinidon-ethyl, fluazolate,flumiclorac-pentyl, flumioxazin, fluthiacet-methyl, oxadiargyl,oxadiazon, pentoxazone, profluazol, pyraflufen-ethyl, pyrazogyl,sulfentrazone and thidiazimin.

Additionally, the present invention is further directed to a process forcontrolling the growth of or killing unwanted plants comprising dilutinga liquid concentrate herbicidal composition comprising at least two ormore herbicidal active ingredients, one of which is an oil-solubleherbicide and the other of which is a water-soluble herbicide, in asuitable volume of water to form a plant treatment composition; and,applying said plant treatment composition to the foliage of the unwantedplants.

Still further, the present invention is directed to compositions asdescribed above that have a viscosity of not greater than about 1000 cPsat 10° C., that have a cloud point not lower than about 50° C. and thatexhibit substantially no crystallization or phase separation when storedat a temperature of from about 10° to about 30° C. for a period of about30 days. Further, the above compositions provide for high loading ofwater-soluble herbicides. For example, herbicidal effectiveconcentrations of the water-soluble herbicide N-(phosphonomethyl)glycinecan be as high as 360 to about 500 g a.e./l in the stable compositionsof the invention.

Other objects and features of this invention will be in part apparentand in part pointed out hereinafter.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In accordance with the present invention, stable coformulations of anoil-soluble herbicide and a water-soluble herbicide have beendiscovered. In one embodiment, a liquid composition of the inventioncomprises an oil-in-water microemulsion having a continuous aqueousphase and a discontinuous oil phase. The water-soluble herbicide ispresent in solution in the continuous aqueous phase of themicroemulsion, and the oil-soluble herbicide is present in solution inthe discontinuous oil phase of the microemulsion. Compositions of thepresent invention provide for an increased weed control spectrum, morerapid burndown, early symptomology and are relatively easy to use.

It is important to note that although the description of the preferredembodiments are directed to stable microemulsions of the presentinvention, the principles disclosed herein are equally applicable to thepreparation of stable oil-in-water emulsions, water-in-oil emulsions,macroemulsions, suspensions or suspoemulsions wherein at least twoherbicidal active ingredients, one of which is a water-soluble herbicideand the other of which is an oil-soluble herbicide, are coformulated ina stable herbicidal composition. Thus, liquid concentrate compositionsof the present invention can be oil-in-water macroemulsions ormicroemulsions, water-in-oil emulsions or water-in-oil-in-water multipleemulsions. Further, all types of concentrate formulations havingcharacteristics of an emulsion, including suspoemulsions, are possiblewithin the invention.

Preferably, the composition is a herbicidal concentrate, i.e., it isnormally diluted in a suitable volume of water before application, forexample, by spraying onto the foliage of plants. Typically, aconcentrate composition contains at least about 5% by weight and up toabout 50% by weight of herbicidal active ingredients. Stated anotherway, the combined concentration of the water-soluble herbicide and theoil-soluble herbicide comprises at least about 5% and up to about 50% byweight of the composition. Preferably, the combined concentration of thewater-soluble herbicide and the oil-soluble herbicide comprises at leastabout 10% by weight of the composition, more preferably at least about20% by weight.

Compositions of the invention have a viscosity of not greater than about1000 cPs at 10° C., more preferably, a viscosity of not greater thanabout 500 cPs at 10° C., even more preferably not greater than 250 cPsat 10° C. Further, compositions of the invention have a cloud point notlower than about 50° C. and preferably exhibit substantially nocrystallization or phase separation when stored at a temperature of fromabout 10° to about 30° C. for a period of about 30 days. Morepreferably, a composition of the invention shows substantially nocrystallization or phase separation for a period of at least about 180days when stored at a temperature of about 10° to about 30° C. Morepreferably, substantially no crystallization or phase change occurs in acomposition of the invention when stored for a period of at least about30 days at storage temperatures of from about −10° to about 40° C.; mostpreferably for a period of at least about 180 days.

The aqueous phase of a composition of the invention comprises waterhaving the selected water-soluble herbicide dissolved therein. The term“water-soluble” as used herein in relation to a herbicide or saltthereof means having a solubility in deionized water at 20° C. of notless than about 50 g/l. Preferred water-soluble herbicides have asolubility in deionized water at 20° C. of not less than about 200 g/l.Particularly preferred water-soluble herbicides have a herbicidal activeacid or anionic moiety and are most usefully present in a composition ofthe invention in the form of one or more water-soluble salts. Theaqueous phase can optionally contain, in addition to the water-solubleherbicide, other salts contributing to the ionic strength of the aqueousphase.

A particularly preferred group of water-soluble herbicides are thosethat are normally applied post-emergence to the foliage of plants. Whilethe invention is not limited to any particular class of foliar-appliedwater-soluble herbicide, it has been found to provide useful benefitsfor compounds that rely at least in part for their herbicidaleffectiveness on systemic movement in plants. Systemic movement inplants can take place via apoplastic (non-living) pathways, includingwithin xylem vessels and in intercellular spaces and cell walls, viasymplastic (living) pathways, including within phloem elements and othertissues composed of cells connected symplastically by plasmodesmata, orvia both apoplastic and symplastic pathways. For foliar-applied systemicherbicides, the most important pathway is the phloem, and the presentinvention is believed to provide the greatest benefits where thewater-soluble herbicide is phloem-mobile. However, compositions of theinvention can also be useful where the water-soluble herbicide isnon-systemic, as in the case of paraquat.

Water-soluble herbicides suitable for use in compositions of theinvention include acifluorfen, acrolein, amitrole, asulam, benazolin,bentazon, bialaphos, bromacil, bromoxynil, chloramben, chloroaceticacid, clopyralid, 2,4-D, 2,4-DB, dalapon, dicamba, dichlorprop,difenzoquat, diquat, endothall, fenac, fenoxaprop, flamprop,flumiclorac, fluoroglycofen, flupropanate, fomesafen, fosamine,glufosinate, glyphosate, imazameth, imazamethabenz, imazamox, imazapic,imazapyr, imazaquin, imazethapyr, ioxynil, MCPA, MCPB, mecoprop,methylarsonic acid, naptalam, nonanoic acid, paraquat, picloram,quinclorac, sulfamic acid, 2,3,6-TBA, TCA, triclopyr and water-solublesalts thereof.

Phloem-mobile herbicides that are preferred for use in compositions ofthe invention include but are not limited to aminotriazole, asulam,bialaphos, clopyralid, dicamba, glufosinate, glyphosate, imidazolinonessuch as imazameth, imazamethabenz, imazamox, imazapic, imazapyr,imazaquin and imazethapyr, phenoxies such as 2,4-D, 2,4-DB, dichlorprop,MCPA, MCPB and mecoprop, picloram and triclopyr. A particularlypreferred group of water-soluble herbicides are salts of bialaphos,glufosinate and glyphosate. Another particularly preferred group ofwater-soluble herbicides are salts of imidazolinone herbicides.

Compositions of the invention can optionally contain more than onewater-soluble herbicide in solution in the aqueous phase.

An especially preferred water-soluble herbicide useful in a compositionof the present invention is glyphosate, the acid form of which isalternatively known as N-(phosphonomethyl)glycine. For example,glyphosate salts useful in compositions of the present invention aredisclosed in U.S. Pat. Nos. 3,799,758 and 4,405,531. Glyphosate saltsthat can be used according to the present invention include but are notrestricted to alkali metal, for example sodium and potassium, salts;ammonium salt; C₁₋₆ alkylammonium, for example dimethylammonium andisopropylammonium, salts; C₁₋₆ alkanolammonium, for examplemonoethanolammonium, salt; C₁₋₆ alkylsulfonium, for exampletrimethylsulfonium, salts; and mixtures thereof. TheN-phosphonomethylglycine molecule has three acid sites having differentpKa values; accordingly mono-, di- and tribasic salts, or any mixturethereof, or salts of any intermediate level of neutralization, can beused.

The oil phase of a composition of the present invention comprises asolvent having an oil-soluble herbicidal active ingredient dissolvedtherein. Oil-soluble herbicides suitable for use in compositions of thepresent invention include but are not limited to acetochlor, aclonifen,alachlor, ametryn, amidosulfuron, anilofos, atrazine, azafenidin,azimsulfuron, benfluralin, benfuresate, bensulfuron-methyl, bensulide,benzfendizone, benzofenap, bifenox, bromobutide, bromofenoxim,butachlor, butafenacil, butamifos, butralin, butroxydim, butylate,cafenstrole, carfentrazone-ethyl, carbetamide, chlomethoxyfen,chlorbromuron, chloridazon, chlorimuron-ethyl, chlorotoluron,chlornitrofen, chlorotoluron, chlorpropham, chlorsulfuron,chlorthal-dimethyl, chlorthiamid, cinidon-ethyl, cinmethylin,cinosulfuron, clethodim, clodinafop-propargyl, clomazone, clomeprop,cloransulam-methyl, cyanazine, cycloate, cyclosulfamuron, cycloxydim,cyhalofop-butyl, daimuron, desmedipham, desmetryn, dichlobenil,diclofop-methyl, diflufenican, dimefuron, dimepiperate, dimethachlor,dimethametryn, dimethenamid, dinitramine, dinoterb, diphenamid,dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron,fluazifop-butyl, fluazifop-P-butyl, fluazolate, fluchloralin,flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, fluoroglycofen-ethyl, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, fomesafen,graminicides, halosafen, halosulfuron, haloxyfop, hexazinone,imazosulfuron, indanofan, isoproturon, isouron, isoxaben, isoxaflutole,isoxapyrifop, lactofen, lenacil, linuron, mefenacet, metamitron,metazachlor, methabenzthiazuron, methyldymron, metobenzuron,metobromuron, metolachlor, metosulam, metoxuron, metribuzin,metsulfuron, molinate, monolinuron, naproanilide, napropamide, neburon,nicosulfuron, norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon,oxasulfuron, oxyfluorfen, pebulate, pendimethalin, pentanochlor,pentoxazone, phenmedipham, piperophos, pretilachlor, primisulfuron,prodiamine, profluazol, prometon, prometryn, propachlor, propanil,propaquizafop, propazine, propham, propisochlor, propyzamide,prosulfocarb, prosulfuron, pyraflufen-ethyl, pyrazogyl, pyrazolynate,pyrazosulfuron-ethyl, pyrazoxyfen, pyributicarb, pyridate,pyriminobac-methyl, quinclorac, quinmerac, quizalofop, quizalofop-P,rimsulfuron, sethoxydim, siduron, simazine, simetryn, sulcotrione,sulfentrazone, sulfometuron, sulfosulfuron, tebutam, tebuthiuron,tepraloxydim, terbacil, terbumeton, terbuthylazine, terbutryn,thenylchlor, thiazopyr, thidiazimin, thifensulfuron, thiobencarb,tiocarbazil, tralkoxydim, triallate, triasulfuron, tribenuron,trietazine, trifluralin, triflusulfuron and vernolate.

Preferred oil-soluble herbicides for use in a composition of theinvention include but are not limited to acetochlor, aclonifen,alachlor, ametryn, amidosulfuron, anilofos, atrazine, azafenidin,azimsulfuron, benfluralin, benfuresate, bensulfuron-methyl, bensulide,benzfendizone, benzofenap, bromobutide, bromofenoxim, butachlor,butafenacil, butamifos, butralin, butroxydim, butylate, cafenstrole,carfentrazone-ethyl, carbetamide, chlorbromuron, chloridazon,chlorimuron-ethyl, chlorotoluron, chlornitrofen, chlorotoluron,chlorpropham, chlorsulfuron, chlorthal-dimethyl, chlorthiamid,cinidon-ethyl, cinmethylin, cinosulfuron, clethodim,clodinafop-propargyl, clomazone, clomeprop, cloransulam-methyl,cyanazine, cycloate, cyclosulfamuron, cycloxydim, cyhalofop-butyl,daimuron, desmedipham, desmetryn, dichlobenil, diclofop-methyl,diflufenican, dimefuron, dimepiperate, dimethachlor, dimethametryn,dimethenamid, dinitramine, dinoterb, diphenamid, dithiopyr, diuron,EPTC, esprocarb, ethalfluralin, ethametsulfuron-methyl, ethofumesate,ethoxysulfuron, etobenzanid, fenoxaprop-ethyl, fenuron, flamprop-methyl,flazasulfuron, fluazifop-butyl, fluazifop-P-butyl, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, graminicides,halosulfuron, haloxyfop, hexazinone, imazosulfuron, indanofan,isoproturon, isouron, isoxaben, isoxaflutole, isoxapyrifop, lenacil,linuron, mefenacet, metamitron, metazachlor, methabenzthiazuron,methyldymron, metobenzuron, metobromuron, metolachlor, metosulam,metoxuron, metribuzin, metsulfuron, molinate, monolinuron, naproanilide,napropamide, neburon, nicosulfuron, norflurazon, orbencarb, oryzalin,oxadiargyl, oxadiazon, oxasulfuron, pebulate, pendimethalin,pentanochlor, pentoxazone, phenmedipham, piperophos, pretilachlor,primisulfuron, prodiamine, profluazol, prometon, prometryn, propachlor,propanil, propaquizafop, propazine, propham, propisochlor, propyzamide,prosulfocarb, prosulfuron, pyraflufen-ethyl, pyrazogyl, pyrazolynate,pyrazosulfuron-ethyl, pyrazoxyfen, pyributicarb, pyridate,pyriminobac-methyl, quinclorac, quimnerac, quizalofop, quizalofop-P,rimsulfuron, sethoxydim, siduron, simazine, simetryn, sulcotrione,sulfentrazone, sulfometuron, sulfosulfuron, tebutam, tebuthiuron,tepraloxydim, terbacil, terbumeton, terbuthylazine, terbutryn,thenylchlor, thiazopyr, thidiazimin, thifensulfuron, thiobencarb,tiocarbazil, tralkoxydim, triallate, triasulfuron, tribenuron,trietazine, trifluralin, triflusulfuron and vernolate.

Another class of preferred oil-soluble herbicides for use in acomposition of the invention are protoporyphinogen oxidase inhibitor(PPO) herbicides. PPO herbicides are known to affect plants byinhibiting protoporphyrinogen oxidase in chloroplasts, therebydisrupting photosynthesis and other biological processes and causingearly symptoms of tissue necrosis in plants. General classes of PPOherbicides include diphenylether herbicides (e.g., bifenox,chlomethoxyfen, fluoroglycofen-ethyl, fomesafen, halosafen, lactofen andoxyfluorfen); phenylpyrazoles (e.g., fluazolate and pyraflufen-ethyl);N-phenylphthalimides (e.g., cinidon-ethyl, flumioxazin andflumiclorac-pentyl); thiadiazoles (e.g., fluthiacet-methyl andthidiazimin); oxadiazoles (e.g., oxadiazon and oxadiargyl);triazolinones (e.g., azafenidin, carfentrazone-ethyl and sulfentrazone);oxazolidinediones (e.g., pentoxazone); pyrimidindiones (e.g.,benzfendizone and butafencil); pyrazogyl and profluazol.

A particularly preferred class of PPO herbicides are the triazolinones.Triazolinone herbicides are known to provide good control of broadleafweeds but are less efficacious in controlling grasses. Suitabletriazolinone herbicides for use in compositions of the invention aredescribed generally in U.S. Pat. Nos. 5,217,520 and 5,125,958 to Possand U.S. Pat. No. 4,818,275 to Theodoridis, all of which are herebyincorporated herein by reference. A triazolinone herbicide suitable foruse in a composition of the invention can be a compound of the structureshown in the following formula:

or a tautomer thereof, wherein R¹ is haloalkyl; R² is halogen or loweralkyl; R³ is —CH₂CHClCO₂R⁴ or —NHSO₂R⁵; R⁴ is alkyl,alkoxycarbonylalkyl, cycloalkyl, benzyl, chlorobenzyl, alkylbenzyl, orhaloalkylbenzyl; R⁵ is alkyl, haloalkyl, dialkylamino, carboxymethyl,hydroxy, or aryl; X is hydrogen, halogen, alkyl, alkoxy, haloalkyl, ornitro; and Y is hydrogen, halogen, alkyl, alkoxy, haloalkyl,haloloweralkylsulfinyl, or haloloweralkoxy.

In a preferred composition, R¹ is difluoromethyl and R² is lower alkyl,more preferably C₁ to about C₅ alkyl, and still more preferably methyl.R⁴ is preferably alkyl or alkoxy, more preferably alkyl, still morepreferably C₁ to about C₅ alkyl, and most preferably ethyl. R⁵ ispreferably alkyl, more preferably C₁ to about C₅ alkyl, and mostpreferably methyl. X is preferably a halogen and more preferably X isfluoro or chloro. Y is preferably a halogen, more preferably chloro.When R³ is —CH₂CHClCO₂R⁴, the triazolinone herbicide is a triazolinoneacid ester herbicide. A particularly preferred triazolinone herbicide iscarfentrazone-ethyl having a structure as follows:

When R³ is —NHSO₂R⁵, the triazolinone herbicide is a triazolinonesulfonamide herbicide. Another particularly preferred triazolinoneherbicide is sulfentrazone having the following structure:

In a composition of the invention, the herbicidal active ingredients aregenerally present in an amount which is biologically effective when thecomposition is diluted in a suitable volume of water and applied to thefoliage of a susceptible plant. Typically, the oil-soluble herbicide ispresent in a concentration such that the weight ratio of water-solubleherbicide to oil-soluble herbicide ranges from about 190:1 to about 1:1.For example, when the oil-soluble herbicide is a PPO herbicide such as atriazolinone, the weight ratio of triazolinone to water-solubleherbicide ranges from about 190:1 to about 19:1. In any case, theconcentration of the oil-soluble herbicide in the composition as a wholeis about 0.1% to about 25% by weight. In preferred compositions, theconcentration of the oil-soluble herbicide is about 0.1% to about 5% byweight, for example about 0.2% to about 2%, by weight.

A key to the present invention is to select as the solvent for theoil-soluble herbicide, i.e., as the basis for the oil phase, an organicliquid having the following properties. First, the solvent must besubstantially immiscible with water. Second, the affinity of the solventfor the oil-soluble herbicide in question must be such thatsubstantially all of the oil-soluble herbicide is partitioned in the oilphase and substantially none is partitioned in the aqueous phase. Oneskilled in the art will readily be able to determine whether aparticular organic solvent meets this second criterion for theoil-soluble herbicide in question by following any standard testprocedure for determining partition of a compound (in this case, theoil-soluble herbicide) between water and the organic solvent.

For example, one such test procedure comprises the following steps.

1. A solution of the oil-soluble herbicide is prepared in the organicsolvent at as high a concentration as possible up to 15% by weight.

2. An aliquot of 10 g of this solution is added to 90 g water in a glassbottle, which is shaken on a mechanical shaker for 4 hours at ambienttemperature.

3. The contents of the glass bottle are permitted to phase separate for4 days.

4. Subsamples of the resulting oil and water phases are taken andanalyzed by HPLC to determine concentrations C_(O) and C_(W) in the oiland water phases respectively. The subsample of the water phase ispreferably centrifuged before analysis to remove traces of organicsolvent.

5. A partition coefficient, analogous to octanol-water partitioncoefficient P, is calculated as C_(O)/C_(W). The partition coefficientis conveniently expressed as a logarithm.

In many cases the concentration of the oil-soluble herbicide in thewater phase will be below the detection limit of the HPLC method. Inother cases, traces of the organic solvent are found in the water phase,even after centrifugation, so that the apparent concentration ofoil-soluble herbicide observed in the water phase is misleadingly high.In such cases, a published value for solubility in water of theoil-soluble herbicide in question can be used in place of C_(W) forcalculation of the partition coefficient.

The organic solvent is selected such that the oil-soluble herbicideexhibits a partition coefficient such that log(C_(O)/C_(W)) is about 4or greater, preferably about 5 or greater. Preferably the oil-solubleherbicide is soluble in the organic solvent by at least about 5% byweight, more preferably by at least about 10% by weight and mostpreferably by at least about 15% by weight. Generally, organic solventshaving a higher solubility of the oil-soluble herbicide therein are moresuitable, provided the organic solvent is substantially immiscible withwater.

Organic solvents useful in compositions of the present inventionpreferably have a flash point above about 35° C., more preferably aboveabout 90° C., and are preferably not antagonistic to the herbicidaleffectiveness of any of the herbicidal active ingredients of thecomposition. Examples of suitable solvents for use in the presentinvention include naphthalenic aromatic solvents such as Aromatic 100,Aromatic 150 or Aromatic 200, commercially available from Exxon MobilChemical of Houston, Tex. or Sure Sol 225, commercially available fromKoch Specialty Chemical Co. of Houston, Tex.; and alkyl acetates withhigh solvency, such as Exxate™ 1000, also available from Exxon MobilChemical. In particular, when the water-soluble herbicide is a salt ofglyphosate, an aromatic solvent is especially preferred. Useful aromaticsolvents include benzene, toluene, o-xylene, m-xylene, p-xylene,mesitylene, naphthalene, bis-(α-methylbenzyl)xylene, phenylxylene andcombinations thereof. Other useful solvents include substituted aromaticsolvents such as chlorobenzene or ortho-dichlorobenzene.

The amount of the selected organic solvent to be used is important.Clearly the amount must be sufficient to completely dissolve theoil-soluble herbicide. Even for an organic solvent in which theoil-soluble herbicide is highly soluble, the weight ratio of organicsolvent to oil-soluble herbicide should not be less than about 3:1. Iftoo small an amount of organic solvent is used, protection of theoil-soluble herbicide from water can be compromised, leading toincreased rates of chemical degradation. The weight ratio of organicsolvent to oil-soluble herbicide can be much higher than 3:1, buteconomics and environmental considerations typically militate againstexcessively high amounts of organic solvent. Thus, an upper limit of theweight ratio for practical purposes is about 75:1. In preferredcompositions of the invention, the weight ratio of organic solvent tooil-soluble herbicide is about 3:1 to about 60:1, more preferably about5:1 to about 50:1.

A composition of the invention further comprises one or moresurfactants. As indicated above, these surfactants can function asemulsifying agents, dispersing agents and/or adjuvants for enhancingherbicidal efficacy. However, the presence of surfactants can bedetrimental to the stability of a microemulsion as surfactants canfacilitate contact of the oil-soluble herbicide with water, therebypromoting chemical degradation of the oil-soluble herbicide. Thecompositions of the invention contain one or more surfactants present ina concentration sufficient to provide acceptable physical stability ofthe composition, and provide acceptable dispersion of the compositionupon dilution thereof in a suitable volume of water for application toplants. Therefore, as an important feature of the present invention, ithas been discovered that, when one or more emulsifying agents and one ormore dispersing agents are selected in accordance with the invention,chemical degradation can be kept to an acceptable minimum by includingless than about 10% by weight of the emulsifying agent(s) and less thanabout 5% of the dispersing agent(s) in the composition. Preferably theamount of all surfactants in the composition is less than about 12% byweight, and more preferably from about 4% to less than about 12%.Ideally, the amount of surfactants included is not substantially morethan the minimum needed for acceptable physical stability and acceptabledispersibility in water. Minimum levels of emulsifying and dispersingagents can readily be determined by one skilled in the art as indicatedabove.

A composition of the invention includes at least one surfactant which isan emulsifying agent. The emulsifying agent preferably has a tertiaryamine functionality. Preferred tertiary amine surfactants have ahydrophobic moiety comprising a linear or branched saturated orunsaturated aliphatic hydrocarbyl group having about 8 to about 22carbon atoms, this moiety being referred to herein as an “alkyl” groupconsistent with conventional use of the term “alkyl” insurfactant-related literature. Such tertiary amine surfactants typicallyalso enhance the herbicidal effectiveness of the composition by variousmeans, including assisting adherence to, and thereby retention on, plantfoliage of the spray composition obtained by diluting the composition inwater, and facilitating penetration of the active ingredients throughcuticles on the surface of plant foliage. This is especially true wherethe water-soluble herbicide is a salt of glyphosate.

Quaternary ammonium surfactants can also be effective emulsifiers andprovide good herbicidal efficacy enhancement; however, quaternaryammonium surfactants are not preferred in compositions of the inventionbecause, at least when present in large amounts, they promote increasedrates of chemical degradation of the oil-soluble herbicide. Withoutbeing bound to a particular theory, it is believed that the increasedchemical degradation associated with the presence of quaternary ammoniumsurfactants results from their effectiveness in facilitating transfer ofthe oil-soluble herbicide from the oil phase to the aqueous phase.Highly water-soluble quaternary ammonium surfactants such asbenzalkonium chloride (a mixture of alkyl dimethyl benzyl ammoniumchlorides) are less troublesome in this regard than quaternary ammoniumsurfactants that are other than water-soluble, such as polyoxyethylene(2) N-methyl alkylammonium chlorides (N,N-bis(hydroxyethyl)-methylalkylammonium chlorides). Compositions of the invention preferablycontain no substantial amount of quaternary ammonium surfactants thatare water-insoluble.

Tertiary amine surfactants for use as the emulsifying agent(s) arepreferably selected from polyoxyethylene (2-20) tertiary alkylamines andpolyoxyethylene (2-20) tertiary alkyletheramines. In particularlypreferred compositions of the invention, the alkyl chains of thesesurfactants have about 12 to about 18 carbon atoms. Often the alkylchains are derived from natural oils or fats such as coconut oil,soybean oil or beef tallow, and the resulting surfactants thereforetypically contain a variety of alkyl chain lengths and degrees ofunsaturation. Preferred tertiary alkylamines for use in the presentinvention include polyoxyethylene (2-10) cocoamine and polyoxyethylene(2-10) tallowamine, which are commercially available from manysurfactant suppliers. For example, Ethomeen™ C15 (polyoxyethylene (5)cocoamine) and Ethomeen™ T15 (polyoxyethylene (5) tallowamine) are twoof such tertiary alkylamines commercially available from Akso NobelSurface Chemistry LLC of Chicago, Ill. Suitable polyoxyethylenealkyletheramines for use in compositions of the invention are disclosedin U.S. Pat. No. 5,750,468 to Wright et al. In preferred compositions ofthe invention, it will often be found desirable to include at least twotertiary amine surfactants, one being more hydrophilic than the other,for example polyoxyethylene (5) tallowamine and polyoxyethylene (2)cocoamine respectively.

The minimum amount of emulsifying agent(s) required to provideacceptable physical stability depends, among other things, on the amountof organic solvent present, which depends in turn on the amount ofoil-soluble herbicide present. Typically, the amount of emulsifyingagent(s) in compositions of the invention ranges from about 3% to about10% by weight, more preferably about 3% to about 8% by weight, and evenmore preferably about 3% to about 6% by weight.

For some oil-soluble herbicides, it has been found that quaternaryalkylammonium chloride surfactants are more effective emulsifying agentsthan the corresponding tertiary alkylamines. For example,polyoxyethylene (2-5) N-methyl alkylammonium chlorides are veryeffective emulsifiers. However, as indicated above, these quaternaryammonium surfactants are unacceptable at relatively high concentrationbecause they promote chemical degradation of the oil-soluble herbicide.Yet, when tertiary amines alone are used, acceptable physical stabilityis not always achievable.

A solution to this problem lies in the surprising discovery thatinclusion of a stabilizing agent, such as a water-soluble chloridesurfactant, substantially dispersed in and associated with the aqueousphase can provide enhanced physical stability when tertiary aminesurfactants are used as emulsifiers. In particular, water-solublequaternary ammonium chloride surfactants such as benzalkonium chlorideare preferred. Without being held to a particular theory, it has beenfound that such water-soluble quaternary ammonium chloride surfactantshave a lesser tendency to promote chemical degradation of theoil-soluble herbicide than other, less water-soluble quaternary ammoniumchlorides such as polyoxyethylene (2-5) N-methyl alkylammonium chloridesand thus, are acceptable ingredients in compositions of the invention.However, it is nonetheless preferred that the amount of the stabilizingagent does not exceed about 6% by weight of the composition. A minimumeffective stabilizing amount of a stabilizing agent can be determined byroutine evaluation of physical stability in any particular situation.Preferred amounts of such a stabilizing agent, for example benzalkoniumchloride, are about 1% to about 6%, more preferably about 1% to about4%, by weight of the composition.

Even more surprisingly, it has been found that physical stability can beenhanced by including a non-surfactant stabilizing agent that issubstantially dispersed in and associated with the aqueous phase ofcompositions of the invention. For example, low molecular weight (C₁₋₆)organic ammonium halides, preferably (C₁₋₆) organic ammonium chloridessuch as isopropylammonium chloride, can be used, as can ammoniumchloride. Alkali metal halides, preferably alkali metal chlorides suchas sodium chloride or potassium chloride are also effective, as ishydrochloric acid. Where the water-soluble herbicide is a salt ofglyphosate, preferred water-soluble chlorides are ammonium chloride,sodium chloride and hydrochloric acid. Hydrochloric acid can beespecially useful where a downward adjustment of the pH of the aqueousphase is desired. An effective stabilizing amount of a water-solublechloride in any particular situation can be determined by routineevaluation of physical stability as indicated previously. Where used,preferred amounts of low molecular weight organic ammonium chlorides,ammonium chloride, alkali metal chlorides and/or hydrochloric acid arethose providing about 0.5% to about 2.5% chloride ion by weight of thecomposition.

Compositions of the invention may further contain one or more dispersingagents. Generally, any nonionic surfactant known to be effective as adispersing agent for liquid concentrate herbicidal formulations can beused as a dispersing agent in a composition of the invention. However,the dispersing agent is preferably one or more surfactants selected frompolyoxyethylene (2-20) alkylethers and alkylphenylethers, the term“alkyl” having the same meaning as in the context of the tertiary aminesurfactants described above. Preferably, the amount of dispersing agentsin a composition of the invention range from about 0.5% to about 5% byweight, and more preferably from about 0.5% to about 3% by weight, ofthe composition.

As used herein, it is to be noted that an amount of the selectedemulsifying agent(s) “sufficient to provide acceptable physicalstability of the composition” can be readily determined by one of skillin the art by routine evaluation of a range of compositions havingdiffering amounts of the emulsifying agent(s). Typically, physicalstability of the composition is acceptable if no significant phaseseparation is evident following storage for at least 7 days at anytemperature in the range from about 0° C. to about 40° C. Where thecomposition is one that additionally requires the presence of awater-soluble chloride for acceptable physical stability, routineevaluation of differing amounts of the emulsifying agent(s) is conductedin the presence of such water-soluble chloride.

Further, a “stabilizing” amount of one or more selected water-solublechlorides as used above is an amount that provides acceptable physicalstability of the compositions as defined above, when present along withan emulsifying agent(s) in an amount insufficient on its own to providesuch stability. One of skill in the art can readily determine such astabilizing amount by routine evaluation of a range of compositionshaving differing amounts of the selected chloride(s).

It is to be further noted that, as used above, an amount of the selecteddispersing agent(s) “sufficient to provide acceptable dispersion of thecomposition upon dilution thereof in a suitable volume of water forapplication to plants” can readily be determined by one of skill in theart by routine evaluation of a range of compositions having differingamounts of the selected dispersing agent(s). A suitable volume of wateris that which upon dilution of the composition provides an applicationtreatment composition having a concentration of active ingredientsadequate to kill or control susceptible plants if applied to foliage ofsuch plants. Dispersion of the composition in such a volume of water isacceptable if no visible aggregation or flocculation of water-insolubleingredients is observed. Therefore, an amount of the selected dispersingagent(s) “not sufficient to destabilize the composition” is an amountlower than that which results in the composition losing the acceptablephysical stability it has in the absence of the dispersing agent(s).Such an amount can readily be determined by one of skill in the art byroutine evaluation of a range of compositions having differing amountsof the selected dispersing agent(s).

Compositions of the invention can optionally contain additional desiredagriculturally acceptable ingredients, including surfactants of classesother than those defined above. Standard reference sources from whichone of skill in the art can select suitable surfactants, withoutlimitation to the above mentioned classes, include Handbook ofIndustrial Surfactants, Second Edition (1997) published by Gower,McCutcheon 's Emusifiers and Detergents, North American andInternational Editions (1997) published by MC Publishing Company, andInternational Cosmetic Ingredient Dictionary, Sixth Edition (1995)Volumes 1 and 2, published by the Cosmetic, Toiletry and FragranceAssociation.

Other optional components of compositions of the invention includeagents to modify color, viscosity, gelling properties, freezing point,hygroscopicity, caking behavior, dissolution rate, dispersibility, orother formulation characteristics.

In a particularly preferred embodiment of the invention, the pH of theaqueous phase of the composition is in a range that is minimallyconducive to chemical degradation of the oil-soluble herbicide. Thewater-soluble herbicide can, in some cases, naturally provide a pH inthe desired range; in other cases an acid, e.g., hydrochloric acid, orbase, e.g., potassium hydroxide or isopropylamine, can be added toadjust the pH. The effect of pH on degradation of the particularoil-soluble herbicide of choice can be determined by empirical testing,but is often known and available in standard reference sources such asThe Pesticide Manual, 11th Edition (1997), published by the British CropProtection Council.

When an organic solvent is selected for the oil-soluble herbicide inaccordance with the present invention, partition of the oil-solubleherbicide is so overwhelmingly in the oil phase that mean residence timein the aqueous phase of individual molecules of the oil-solubleherbicide is extremely short, and the opportunity for chemicaldegradation of the oil-soluble herbicide is accordingly very small.However, the adjustment of pH as just described is desirable to furtherreduce the potential for chemical degradation and permit the longestpossible shelf-life for the composition.

A process of preparing a composition of the invention comprises mixingthe various ingredients in a suitable vessel. It is important to notethat mixing is not critical to the invention and any order of additionof ingredients is suitable. However, experience to date suggests thatcertain orders of addition in preparing compositions of the inventionrequire less reaction time. Therefore, a presently preferred order ofaddition of the ingredients involves adding all required surfactants toa concentrated aqueous solution of the water-soluble herbicide alongwith an acid or base for pH adjustment, if desired, to form a firstmixture. The oil-soluble herbicide is added to the organic solvent withagitation to form a second mixture. The second mixture is then added tothe first mixture with agitation to form the finished composition.

An alternative order of addition involves mixing a concentrated aqueoussolution of the water-soluble herbicide together with other, optional,water-soluble ingredients including an acid or base for pH adjustment,with agitation to form a first mixture. The oil-soluble herbicide isthen added to the organic solvent with agitation to form a secondmixture. The second mixture is added to the first mixture withagitation, then the surfactants are added. Agitation is continued untila physically stable composition is formed.

In a particularly preferred composition of the invention, theoil-soluble herbicide is carfentrazone-ethyl, a PPO herbicide of thetriazolinone class, and the water-soluble herbicide is a salt ofN-(phosphonomethyl)glycine (“glyphosate”).

Carfentrazone-ethyl, as described in U.S. Pat. No. 5,217,520incorporated herein by reference, and otherwise known as ethylα,2-dichloro-5-(4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl)-4-fluorobenzenepropionate,CAS Registry Number 128639-02-1, is a high-melting solid carboxylic aciduseful for post-emergent control primarily of broadleaf weeds known forits rapid uptake and early symptomology. N-(phosphonomethyl)glycine, onthe other hand, is a widely-used broad-spectrum herbicide that does notnecessarily provide early symptomology. Therefore, coformulations ofcarfentrazone-ethyl and N-(phosphonomethyl)glycine can benefit from thebroad spectrum of control of the N-(phosphonomethyl)glycine while theearly symptoms caused by the carfentrazone-ethyl can serve as a markerindicating whether a given plant has been treated with the combination.Contemplated compositions of the invention comprising a salt ofglyphosate and an oil-soluble triazolinone such as carfentrazone-ethyltypically contain about 50 to about 500 grams per liter of glyphosate,expressed as acid equivalent (g a.e./l). Higher glyphosateconcentrations within this range, for example, about 300 to about 500 ga.e./l are preferred, even more preferably about 360 to about 500 ga.e./l.

Glyphosate (N-phosphonomethylglycine) in its strict sense is an acidcompound, but the word “glyphosate” is used herein in a less restrictivesense, except where the context dictates otherwise, to encompass notonly glyphosate acid but also salts, adducts and esters thereof, andcompounds which are converted to glyphosate in plant tissues or whichotherwise provide glyphosate ions. In most commercial formulations ofglyphosate, the glyphosate is present as a water-soluble salt. In thisrespect, glyphosate is typical of most exogenous chemical substancesthat are acids or that form anions.

Herbicidal salts of glyphosate are disclosed, for example, in U.S. Pat.No. 3,799,758 to Franz, U.S. Pat. No. 3,853,530 to Franz, U.S. Pat. No.4,140,513 to Prill, U.S. Pat. No. 4,315,765 to Large, U.S. Pat. No.4,405,531 to Franz, U.S. Pat. No. 4,481,026 to Prisbylla and U.S. Pat.No. 4,507,250 to Bakel. In most of the salts disclosed, the counterionto glyphosate anion is a relatively low molecular weight,non-amphiphilic cation. Typical of such salts are alkali metal, forexample sodium and potassium, salts; ammonium salt; and salts having anammonium, sulfonium or sulfoxonium cation substituted with 1-3 organicgroups containing in total 1-6 carbon atoms, for exampledimethylammonium, isopropylammonium, ethanolammonium andtrimethylsulfonium salts.

Commercial formulations of glyphosate salts include, for example,Roundup® brand, Accord® brand, Roundup® Ultra brand and Roundup® Xtrabrand herbicides of Monsanto Company, which contain theisopropylammonium salt, Roundup® Dry brand and Rival® brand herbicidesof Monsanto Company, which contain the ammonium salt, Roundup® Geoforcebrand herbicide of Monsanto Company, which contains the sodium salt, andTouchdown® brand herbicide of Zeneca, which contains thetrimethylsulfonium salt.

The selection of application rates relative to providing a desired levelof herbicidal activity for a composition of the invention containing aspecific water-soluble herbicide and a specific oil-soluble herbicide iswithin the skill of the ordinary agricultural technician. One skilled inthe art will recognize that individual plant conditions, weather andgrowing conditions, as well as the specific exogenous chemical substanceselected, can affect the results achieved in using a composition of thepresent invention. Where the water-soluble herbicide is a glyphosatesalt, much information is available in published literature aboutappropriate application rates. Over two decades of glyphosate use andpublished studies relating to such use have provided abundantinformation from which a weed control practitioner can select glyphosateapplication rates that are herbicidally effective on particular speciesat particular growth stages in particular environmental conditions.Generally, preferred application rates for glyphosate are from about 100to about 2500 g a.e./ha, more preferably from about 250 to about 1500 ga.e./ha.

The method of the present invention where the water-soluble herbicide isglyphosate, more particularly a water-soluble glyphosate salt, isapplicable to any and all plant species on which glyphosate isbiologically effective as a herbicide. This encompasses a very widevariety of plant species worldwide. Likewise, compositions of theinvention containing a glyphosate salt can be applied to any and allplant species on which glyphosate is biologically effective. Therefore,for example, compositions of the invention containing glyphosate as anherbicidal active ingredient can be applied to a plant in a herbicidallyeffective amount, and can effectively control one or more plant speciesof one or more of the following genera without restriction: Abutilon,Amaranthus, Artemisia, Asclepias, Avena, Axonopus, Borreria, Brachiaria,Brassica, Bromus, Chenopodium, Cirsium, Commelina, Convolvulus, Cynodon,Cyperus, Digitaria, Echinochloa, Eleusine, Elymus, Equisetum, Erodium,Helianthus, Imperata, Ipomoea, Kochia, Lolium, Malva, Oryza, Ottochloa,Panicum, Paspalum, Phalaris, Phragmites, Polygonum, Portulaca,Pteridium, Pueraria, Rubus, Salsola, Setaria, Sida, Sinapis, Sorghum,Triticum, Typha, Ulex, Xanthium and Zea.

Particularly important annual broadleaf species for which glyphosatecompositions are used are exemplified without limitation by thefollowing: velvetleaf (Abutilon theophrasti), pigweed (Amaranthus spp.),buttonweed (Borreria spp.), oilseed rape, canola, indian mustard, etc.(Brassica spp.), commelina (Commelina spp.), filaree (Erodium spp.),sunflower (Helianthus spp.), morningglory (Ipomoea spp.), kochia (Kochiascoparia), mallow (Malva spp.), wild buckwheat, smartweed, etc.(Polygonum spp.), purslane (Portulaca spp.), russian thistle (Salsolaspp.), sida (Sida spp.), wild mustard (Sinapis arvensis) and cocklebur(Xanthium spp.)

Particularly important annual narrowleaf species for which glyphosatecompositions are used are exemplified without limitation by thefollowing: wild oat (Avena fatua), carpetgrass (Axonopus spp.), downybrome (Bromus tectorum), crabgrass (Digitaria spp.), barnyardgrass(Echinochloa crus-galli), goosegrass (Eleusine indica), annual ryegrass(Lolium multiflorum), rice (Oryza sativa), ottochloa (Ottochloa nodosa),bahiagrass (Paspalum notatum), canarygrass (Phalaris spp.), foxtail(Setaria spp.), wheat (Triticum aestivum) and corn (Zea mays).

Particularly important perennial broadleaf species for which glyphosatecompositions are used are exemplified without limitation by thefollowing: mugwort (Artemisia spp.), milkweed (Asclepias spp.), canadathistle (Cirsium arvense), field bindweed (Convolvulus arvensis) andkudzu (Pueraria spp.).

Particularly important perennial narrowleaf species for which glyphosatecompositions are used are exemplified without limitation by thefollowing: brachiaria (Brachiaria spp.), bernudagrass (Cynodondactylon), yellow nutsedge (Cyperus esculentus), purple nutsedge (C.rotundus), quackgrass (Elymus repens), lalang (Imperata cylindrica),perennial ryegrass (Lolium perenne), guineagrass (Panicum maximum),dallisgrass (Paspalum dilatatum), reed (Phragmites spp.), johnsongrass(Sorghum halepense) and cattail (Typha spp.).

Other particularly important perennial species for which glyphosatecompositions are used are exemplified without limitation by thefollowing: horsetail (Equisetum spp.), bracken (Pteridium aquilinum),blackberry (Rubus spp.) and gorse (Ulex europaeus).

Thus, for example, glyphosate/triazolinone compositions of the presentinvention, and a process for treating plants with such compositions, canbe useful on any of the above species. In a particular contemplatedprocess, a plant treatment composition is formed by diluting acomposition of the invention in a suitable volume of water forapplication to a field. Preferably, a plant treatment compositioncomprising glyphosate and a triazolinone herbicide such ascarfentrazone-ethyl is formed by diluting a composition of the presentinvention in water and the plant treatment composition is applied toweeds or undesired plants for burndown. As glyphosate is generally veryeffective in controlling most grass weeds, the role of the triazolinonein a glyphosate/triazolinone composition is especially to controlbroadleaf weeds and to act as a marker in providing rapid burndown andearly visual symptoms of treatment.

Application of plant treatment compositions to foliage of plants ispreferably accomplished by spraying, using any conventional means forspraying liquids, such as spray nozzles or spinning-disk atomizers.Compositions of the present invention can be used in precision farmingtechniques, in which apparatus is employed to vary the amount ofexogenous chemical substance applied to different parts of a field,depending on variables such as the particular plant species present,plant growth stage, soil moisture status, etc. In one embodiment of suchtechniques, a global positioning system operated with the sprayingapparatus can be used to apply the desired amount of the composition todifferent parts of a field.

A plant treatment composition is preferably dilute enough to be readilysprayed using standard agricultural spray equipment. Suitableapplication rates for the present invention vary depending upon suchfactors as the type and concentration of active ingredient and the plantspecies involved. Useful rates for applying an aqueous composition to afield of foliage can range from about 25 to about 1,000 liters perhectare (l/ha), preferably about 50 to about 300 l/ha, by sprayapplication.

EXAMPLES

The following examples are provided for illustrative purposes only andare not intended to limit the scope of the present invention. In theseexamples, percentage amounts refer to percent by weight unless otherwisenoted.

Examples 1 through 12 utilized Formulation L, available from MonsantoCompany as MON 0139, which consists of 62% by weight of glyphosateisopropylammonium salt (IPA) in aqueous solution with no surfactant as astarting ingredient. Formulation L contains 570 g a.e./l of glyphosate.

Example 1

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.37%¹ ammonium chloride  1.11%2N hydrochloric acid 11.31% Solvent (Aromatic 150) 11.93%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 3.07% Emulsifier (Ethomeen C/15)  2.95% Dispersant (Surfonic L12-6) 2.09% ¹Equivalent to 41.77% glyphosate IPA active ingredient.

Ammonium chloride (0.45 g) was dissolved in 2N hydrochloric acid (4.60g) and the resulting solution was mixed with MON 0139 (27.41 g) to forma first mixture. Carfentrazone-ethyl (0.0739 g) was dissolved inAromatic 150 (4.85 g) to form a second mixture, which was then added tothe first mixture with agitation. Finally, surfactants Ethomeen T/15(1.25 g), Ethomeen C/15 (1.20 g) and Surfonic L12-6 (0.85 g) were addedand the whole composition was stirred, using an overhead electricstirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 2

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.48%¹ ammonium chloride  0.27%water  3.62% 2N hydrochloric acid 11.32% Solvent (Aromatic 150)  2.07%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 3.27% Emulsifier (Ethomeen C/15)  1.26% Dispersant (Surfonic L12-6) 2.07% ¹Equivalent to 41.84% glyphosate IPA active ingredient.

Ammonium chloride (0.11 g) was dissolved in water (1.47 g) and 2Nhydrochloric acid (4.60 g) and the resulting solution was mixed with MON0139 (27.41 g) to form a first mixture. Carfentrazone-ethyl (0.0739 g)was dissolved in Aromatic 150 solvent (4.27 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (1.33 g), Ethomeen C/15 (0.51 g) and SurfonicL12-6 (0.84 g) were added and the whole composition was stirred, usingan overhead electric stirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 3

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 68.29%¹ water  3.31% 2Nhydrochloric acid 11.53% Solvent (Aromatic 150) 10.65%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 4.36% Emulsifier (Ethomeen C/15)  0.00% Dispersant (Surfonic L12-6) 1.67% ¹Equivalent to 42.34% glyphosate IPA active ingredient.

MON 0139 (27.42 g) was mixed with water (1.33 g) and 2N hydrochloricacid (4.63 g) to form a first mixture. Carfentrazone-ethyl (0.0740 g)was dissolved in Aromatic 150 solvent (4.28 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (1.75 g) and Surfonic L12-6 (0.67 g) wereadded and the whole composition was stirred, using an overhead electricstirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 4

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.79%¹ water  4.10% 2Nhydrochloric acid 11.37% Solvent (Aromatic 150) 10.57%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 4.33% Emulsifier (Ethomeen C/15)  0.00% Dispersant (Surfonic L12-6) 1.66% ¹Equivalent to 42.03% glyphosate IPA active ingredient.

MON 0139 (27.42 g) was mixed with water (1.66 g) and 2N hydrochloricacid (4.60 g) to form a first mixture. Carfentrazone-ethyl (0.0740 g)was dissolved in Aromatic 150 solvent (4.28 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (1.75 g), and Surfonic L12-6 (0.67 g) wereadded and the whole composition was stirred, using an overhead electricstirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 5

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.84%¹ water  2.47% 2Nhydrochloric acid 11.41% Solvent (Aromatic 150) 12.02%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 4.33% Emulsifier (Ethomeen C/15)  0.00% Dispersant (Surfonic L12-6) 1.76% ¹Equivalent to 42.06% glyphosate IPA active ingredient.

MON 0139 (27.42 g) was mixed with water (1.00 g) and 2N hydrochloricacid (4.61 g) to form a first mixture. Carfentrazone-ethyl (0.0740 g)was dissolved in Aromatic 150 solvent (4.86 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (1.75 g) and Surfonic L12-6 (0.71 g) wereadded and the whole composition was stirred, using an overhead electricstirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 6

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.71%¹ water  2.30% 2Nhydrochloric acid 11.43% Solvent (Aromatic 150) 10.56%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 6.27% Sodium chloride  0.96% Dispersant (Surfonic L12-6)  0.59%¹Equivalent to 41.98% glyphosate IPA active ingredient.

Sodium chloride (0.39 g) was dissolved in water (0.93 g) and 2Nhydrochloric acid (4.63 g) and the resulting solution was mixed with MON0139 (27.43 g) to form a first mixture. Carfentrazone-ethyl (0.0740 g)was dissolved in Aromatic 150 solvent (4.28 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (2.54 g) and Surfonic L12-6 (0.24 g) wereadded and the whole composition was stirred, using an overhead electricstirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 7

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.89%¹ water  1.91% 2Nhydrochloric acid 11.41% Solvent (Aromatic 150) 12.03%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 5.00% Sodium Chloride  0.40% Dispersant (Surfonic L12-6)  1.19%¹Equivalent to 42.09% glyphosate IPA active ingredient.

Sodium chloride (0.16 g) was dissolved in water (0.77 g) and 2Nhydrochloric acid (4.61 g) and the resulting solution was mixed with MON0139 (27.43 g) to form a first mixture. Carfentrazone-ethyl (0.0740 g)was dissolved in Aromatic 150 solvent (4.86 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (2.02 g) and Surfonic L12-6 (0.48 g) wereadded and the whole composition was stirred, using an overhead electricstirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 8

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.82%¹ water  3.76% 2Nhydrochloric acid 10.39% Solvent (Aromatic 150) 12.01%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 4.01% Sodium Chloride  0.45% Dispersant (Surfonic L12-6)  1.39%¹Equivalent to 42.05% glyphosate IPA active ingredient.

Sodium chloride (0.18 g) was dissolved in water (1.52 g) and 2Nhydrochloric acid (4.20 g) and the resulting solution was mixed with MON0139 (27.42 g) to form a first mixture. Carfentrazone-ethyl (0.0740 g)was dissolved in Aromatic 150 solvent (4.86 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (1.62 g) and Surfonic L12-6 (0.56 g) wereadded and the whole composition was stirred, using an overhead electricstirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 9

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.72%¹ water  5.39% 2Nhydrochloric acid 10.38% Solvent (Aromatic 150) 10.56%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 4.00% Sodium Chloride  0.44% Dispersant (Surfonic L12-6)  1.32%¹Equivalent to 41.99% glyphosate IPA active ingredient.

Sodium chloride (0.18 g) was dissolved in water (2.18 g) and 2Nhydrochloric acid (4.20 g) and the resulting solution was mixed with MON0139 (27.41 g) to form a first mixture. Carfentrazone-ethyl (0.0739 g)was dissolved in Aromatic 150 solvent (4.27 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (1.62 g) and Surfonic L12-6 (0.54 g) wereadded and the whole composition was stirred, using an overhead electricstirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 10

A microemulsion composition was prepared having the followingingredients:

glyphosate IPA salt solution (MON 0139) 67.37%¹ ammonium chloride  1.11%2N hydrochloric acid 11.31% Solvent (Aromatic 150) 11.93%carfentrazone-ethyl (91.2% active)  0.18% Emulsifier (Ethomeen T/15) 3.07% Emulsifier (Ethomeen C/15)  2.95% Dispersant (Surfonic L12-6) 2.09% ¹Equivalent to 41.77% glyphosate IPA active ingredient.

Ammonium chloride (0.11 g) was dissolved in water (1.47 g) and 2Nhydrochloric acid (4.60 g) and the resulting solution was mixed with MON0139 (27.41 g) to form a first mixture. Carfentrazone-ethyl (0.07 g) wasdissolved in Aromatic 150 solvent (4.27 g) to form a second mixture,which was then added to the first mixture with agitation. Finally,surfactants Ethomeen T/15 (1.33 g), Ethomeen C/15 (0.51 g) and SurfonicL12-6 (0.84 g) were added and the whole composition was stirred, usingan overhead electric stirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 50° C.The microemulsion exhibited good dispersion in water.

Example 11

The following example demonstrates the effect of varying the amount ofsolvent used in the formulation on the stability of carfentrazone-ethylin compositions of the present invention. All compositions were preparedas in the Examples above using the glyphosate IPA salt solution MON 0139and carfentrazone-ethyl. The amount and type of solvent was varied as inthe following Table 1. For all of the compositions prepared, fivealiquots were taken and stored in capped glass bottles. Aliquots werestored at 0° C., Room Temperature (approximately 22° C.), 40° C., 50° C.and 60° C. to accelerate any chemical degradation of thecarfentrazone-ethyl that might occur. After storing the aliquots forfour weeks (three weeks for the 60° C. samples), carfentrazone-ethyl wasassayed by HPLC. Assays were compared with those from the freshlyprepared samples of each composition to determine the degree of chemicaldegradation. Results are shown in Table 1 as percentages ofcarfentrazone-ethyl remaining. As indicated in the Table, SS 225represents Sure Sol 225 as the solvent, Ar 150 represents Aromatic 150as the solvent and Ar 200 represents Aromatic 200 as the selectedsolvent. Results represented as “--” indicate that no data was availablefor a particular sample.

TABLE 1 Ar Ar Ar Solvent Type SS 225 SS 225 SS 225 SS 225 150 200 150 %Solvent 1.5 3.2 6.6 8.3 8.3 8.3 10.3  0° C. 94 93 94 98 99 100 100 RoomTemp. 90 90 92 97 99 99 100 40° C. 50 63 80 87 98 96 92 50° C. — — — — —92 92 60° C. — — — — — 90 90

Example 12

This example demonstrates the effect of compositions of the inventionfor controlling broadleaf weeds and grasses. Test were conducted bypreparing a microemulsion composition (Formulation MON 78402) as inExample 1 having the following ingredients:

glyphosate IPA salt solution (MON 0139) 67.80% ammonium chloride/sodiumchloride 1.53% 2N hydrochloric acid 10.39% Solvent (Aromatic 150/200)10.57% carfentrazone-ethyl (91.2% active) 0.18% Emulsifiers (EthomeenT/15 and C/15) 6.06% Dispersant (Surfonic L12-6) 1.58%

The microemulsion composition was applied to a field (1.0 lb a.i./a)having 4-8 inch weeds actively growing. As a comparison, a separatefield test was conducted wherein 0.25% of non-ionic surfactant was addedto the microemulsion composition MON 78402 and applied to a field (1.0lb a.i./a). The formulations were applied to the field using a CO₂backpack with 3 replications per treatment at a spray volume of 10gallons per acre. Burndown was evaluated at 2 to 4 days after treatmentwith a final control evaluation at 21 to 28 days after treatment.

The test was evaluated for control of broadleaf weeds and grasses incomparison to standard burndown data for formulations of Roundup® Ultrabrand herbicide comprising glyphosate IPA salt as the only herbicidalactive ingredient. Broadleaf weed species evaluated included p. lettuce,mustard, w. mustard, f. pennycress, dandelion, c. chickweed, sowthistle,c. primrose, w. buckwheat, henbit, cidweed, c. geranium, horseweed,bittercress, shepardspurse, velvetleaf, r. thistle, p. sida, h.sesbania, p. smartweed, kochia, morninglory, lambsquarter, g. ragweed,c. waterhemp, pigweed, and sicklepod. Grass species evaluated includedannual bluegrass, italian ryegrass, barnyardgrass, downy bromegrass andfoxtail. Effects on glyphosate-tolerant crops such as Roundup®-readycorn, soybeans and cotton were also evaluated. Results are presented inTables 2 and 3 below as percentage enhancement over standardapplications of Roundup® Ultra brand herbicide. Table 2 includes resultsfor the early evaluation at 2 to 4 days after treatment and Table 3presents results for the final evaluation at 21 to 28 days aftertreatment. Results represented as “--” indicate that no data wasavailable for a particular sample.

TABLE 2 MON 78402 MON 78402 + NIS Winter Weeds P. Lettuce 15 — Mustard —35 W. Mustard 5 — F. Pennycress 10 — Dandelion 20 — C. Chickweed −2 —Sowthistle 21 20 C. Primrose 8 5 W. Buckwheat 0 −8 Henbit 4 9 Cudweed 4— C. Geranium 6 9 Horseweed — — Bittercress 10 12 Shepardspurse 24 20Filaree 26 — Spring/Summer Weeds Velvetleaf 41 33 R. Thistle 0 30 P.Sida 13 15 H. Sesbania −5 −7 P. Smartweed 12 25 Kochia 0 15 Morninglory37 30 Lambsquarter 27 25 G. Ragweed — 52 C. Waterhemp — 24 Pigweed 9 —Sicklepod 1 3 Annual Grasses Annual Bluegrass 5 — Italian Ryegrass 0 —Barnyardgrass −1 −1 Downy Bromegrass −2 0 Foxtail 3 7 Roundup ® -readyCrops RR-Corn 5 9 RR-Soybeans 31 25 RR-Cotton 50 40

TABLE 3 MON 78402 MON 78402 + NIS Winter Weeds P. Lettuce 7 — Mustard —35 W. Mustard 1 — F. Pennycress 4 — Dandelion −15 — C. Chickweed 0 —Sowthistle −1 1 C. Primrose −1 12 W. Buckwheat 3 4 Henbit −3 2 Cudweed 0— C. Geranium 12 — Horseweed — — Bittercress 0 0 Shepardspurse 7 13Filaree −15 — Spring/Summer Weeds Velvetleaf 8 3 R. Thistle — −12 P.Sida −5 0 H. Sesbania 3 3 P. Smartweed −4 −3 Kochia 0 −7 Morninglory 1517 Lambsquarter −3 −4 G. Ragweed — −7 C. Waterhemp — — Pigweed 0 0Sicklepod −3 −2 Annual Grasses Annual Bluegrass 5 — Italian Ryegrass 0 —Barnyardgrass −1 −1 Downy Bromegrass −2 0 Foxtail 3 7 Roundup ® -readyCrops RR-Corn 5 9 RR-Soybeans 31 25 RR-Cotton 50 40

Example 13

A microemulsion composition (MON 78481) was prepared having thefollowing composition:

glyphosate potassium salt solution (MON 78623) 76.27%¹ sodium chloride0.36% phosphoric acid 2.87% Solvent (Aromatic 150) 10.38%carfentrazone-ethyl (92.2% active) 0.21% Emulsifier (Ethomeen T/15)1.98% Emulsifier (Ethomeen C/12) 2.03% Dispersant (Surfonic L12-6) 1.57%Water 4.31% Dye (Yellow) 0.01% ¹47.90% glyphosate acid equivalent

Sodium chloride (45.5 g) was dissolved in water (542.5 g) and phosphoricacid (360.5 g) and the resulting solution was mixed with MON 78623(9591.0 g) to form a first mixture. Carfentrazone-ethyl (26.6 g) wasdissolved in Aromatic 150 (1305.6 g) to form a second mixture, which wasthen added to the first mixture with agitation. Finally, surfactantsEthomeen T/15 (248.5 g), Ethomeen C/12 (255.5 g) and Surfonic L12-6(197.5 g) were added and the whole composition was stirred, using anoverhead electric stirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

Example 14

A microemulsion composition (MON 78482) was prepared having thefollowing composition:

glyphosate potassium salt solution (47.8% a.e.) 76.56%¹ sodium chloride0.42% phosphoric acid 2.88% Solvent (Aromatic 150) 10.51%carfentrazone-ethyl (92.2% active) 0.11% Emulsifier (Ethomeen T/15)1.98% Emulsifier (Ethomeen C/12) 2.01% Dispersant (Surfonic L12-6) 1.34%Water 4.19% ¹47.80% glyphosate acid equivalent

Sodium chloride (0.15 g) was dissolved in water (1.50 g) and phosphoricacid (1.03 g). The resulting solution was mixed with a potassiumglyphosate salt solution (27.40 g) comprising 47.80% glyphosate activeingredient to form a first mixture. Carfentrazone-ethyl (0.04 g) wasdissolved in Aromatic 150 (3.76 g) to form a second mixture, which wasthen added to the first mixture with agitation. Finally, surfactantsEthomeen T/15 (0.71 g), Ethomeen C/12 (0.72 g) and Surfonic L12-6 (0.48g) were added and the whole composition was stirred, using an overheadelectric stirrer, under moderate agitation for 30 minutes.

The composition was a clear amber microemulsion that was physicallystable at −10° C., room temperature (approximately 22° C.) and 60° C.The microemulsion exhibited good dispersion in water.

The preceding description of specific embodiments of the presentinvention is not intended to be a complete list of every possibleembodiment of the invention. Persons skilled in this field willrecognize that modifications can be made to the specific embodimentsdescribed here that would be within the scope of the present invention.

What is claimed:
 1. A liquid concentrate herbicidal emulsion compositioncomprising: (i) a water-soluble herbicide in water, the water-solubleherbicide being present in a concentration that is biologicallyeffective when the composition is diluted in a suitable volume of waterand applied to the foliage of a susceptible plant; (ii) an oil-solubleherbicide present in a concentration that is biologically effective whenthe composition is diluted in a suitable volume of water and applied tothe foliage of a susceptible plant; (iii) a stabilizing amount of one ormore water-soluble chlorides selected from hydrochloric acid, alkalimetal chlorides, ammonium chloride, low molecular weight organicammonium chlorides and quaternary ammonium chloride surfactantssufficient to inhibit substantial degradation of the oil-solubleherbicide; and (iv) one or more surfactants present in a concentrationsufficient to provide acceptable physical stability of the emulsion andprovide acceptable dispersion of the emulsion upon dilution thereof in asuitable volume of water for application to plants; wherein theoil-soluble herbicide is selected from the group consisting ofacetochlor, alachlor, ametryn, amidosulfuron, anilofos, atrazine,azafenidin, azimsulfuron, benfluralin, benfuresate, bensulfuron-methyl,bensulide, benzfendizone, benzofenap, bromobutide, bromofenoxim,butachlor, butafenacil, butamifos, butralin, butylate, cafenstrole,carbetamide, chlorbromuron, chloridazon, chlorimuron-ethyl,chlorotoluron, chlorpropham, chlorsulfuron, chlorthal-dimethyl,chlorthiamid, cinidon-ethyl, cinmethylin, cinosulfuron, clomazone,clomeprop, cloransulam-rnethyl, cyanazine, cycloate, cyclosulfamuron,daimuron, desmedipham, desmetryn, dichlobenil, diflufenican, dimefuron,dimepiperate, dirnethachlor, dimethametryn, dimethenamid, dinitramine,dinoterb, diphenamid, dithiopyr, diuron, EPTC, esprocarb, ethalfiuralin,ethametsulifuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,ferioxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanof an, isoproturon, isouron, isoxaben,isoxaiflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulifuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norfiurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanhl, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenyichlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.
 2. Acomposition as set forth in claim 1 wherein the emulsion comprises asuspoemulsion, a microemulsion, or a macroemulsion.
 3. A composition asset forth in claim 1 wherein the combined concentration of thewater-soluble herbicide and the oil-soluble herbicide ranges from about5% to about 50% by weight of the composition.
 4. A composition as setforth in claim 1 wherein the combined concentration of the water-solubleherbicide and the oil-soluble herbicide ranges from about 20% to about50% by weight of the composition.
 5. A composition as set forth in claim1 wherein the weight ratio of water-soluble herbicide to oil-solubleherbicide ranges from about 190:1 to about 1:1.
 6. A composition as setforth in claim 1 wherein the water-soluble herbicide is selected fromthe group consisting of acifluorfen, acrolein, amitrole, asulam,benazolin, bialaphos, bromacil, bromoxynil, chloramben, chloroaceticacid, clopyralid, 2,4-D, 2,4-DB, dalapon, dicamba, dichlorpropdifenzoquat, diquat, endothall, fenac, fenoxaprop, flamprop,flumiclorac, fluoroglycofen, flupropanate, fomesafen, fosamine,glufosinate, glyphosate, imazameth, imazamethabenz, imazamox, imazapic,imazapyr, imazaquin, imazethapyr, ioxynil, MCPA, MCPB, mecoprop,methylarsonic acid, naptalam, nonanoic acid, paraquat, picloram,quinclorac, sulfamic acid, 2,3,6-TBA, triclopyr and water-soluble saltsthereof.
 7. A composition as set forth in claim 1 wherein thewater-soluble herbicide is a salt of glyphosate.
 8. A composition as setforth in claim 7 wherein said composition contains from about 50 toabout 500 grams a.e. glyphosate per liter.
 9. A composition as set forthin claim 7 wherein said composition contains from about 300 to about 500grams a.e. glyphosate per liter.
 10. A composition as set forth in claim7 wherein said composition contains from about 360 to about 500 gramsa.e. glyphosate per liter.
 11. A composition as set forth in claim 7wherein the salt of glyphosate is an alkali metal, ammonium, C1-6alkylammonium, C1-6 alkanolammonium, or C1-6 alkylsulfonium saltthereof.
 12. A composition as set forth in claim 11 wherein the salt ofglyphosate is the isopropylammonium or potassium salt thereof.
 13. Acomposition as set forth in claim 1 wherein the oil-soluble herbicidecomprises a protoporphyrinogen oxidaze inhibitor (PPO) herbicideselected from the group consisting of azafenidin, benzfendizone,butafenacil, cinidon-ethyl, fluazolate, flumiclorac-pentyl, flumioxazin,fluthiacet-methyl, oxadiargyl, oxadiazon, pentoxazone, profluazol,pyraflufen-ethyl, pyrazogyl, sulfentrazone and thidiazimin.
 14. Acomposition as set forth in claim 1 further comprising a substantiallywater-immiscible organic solvent, wherein the organic solvent isselected such that the oil-soluble herbicide has an organicsolvent/water partition coefficient, expressed as a logarithm, of about4 or greater.
 15. A composition as set forth in claim 14 wherein theweight ratio of organic solvent to oil-soluble herbicide ranges fromabout 3:1 to about 75:1.
 16. A composition as set forth in claim 14wherein the weight ratio of organic solvent to oil-soluble herbicideranges from about 3:1 to about 60:1.
 17. A composition as set forth inclaim 14 wherein the weight ratio of organic solvent to oil-solubleherbicide ranges from about 5:1 to about 50:1.
 18. A composition as setforth in claim 14 wherein the organic solvent is an aromatic solvent.19. A composition as set forth in claim 14 wherein the organic solventis selected such that the oil-soluble herbicide has an organicsolvent/water partition coefficient, expressed as a logarithm, of atleast about 5 or greater.
 20. A composition as set forth in claim 1wherein the water-soluble chloride stabilizing agent is present in aconcentration sufficient to provide a concentration of chloride ion offrom about 0.5% to about 2.5% by weight.
 21. A composition as set forthin claim 20 wherein the water-soluble chloride stabilizing agentcomprises ammonium chloride, sodium chloride, hydrochloric acid or acombination thereof.
 22. A composition as set forth in claim 1 whereinthe total concentration of all surfactants present in the composition isless than about 12% by weight.
 23. A composition as set forth in claim 1further comprising one or more surfactants selected from the groupconsisting of polyoxyethylene (2-20) tertiary alkylamines andpolyoxyethylene (2-20) tertiary alkyletheramines.
 24. A composition asset forth in claim 23 wherein said alkylamines and alkyletheramines havealkyl chains having from about 12 to about 18 carbon atoms.
 25. Acomposition as set forth in claim 23 wherein said alkylamine and/oralkyletheramine surfactant(s) comprise about 3% to about 10% by weightof the composition.
 26. A composition as set forth in claim 1 furthercomprising one or more nonionic surfactants selected from the groupconsisting of polyoxyethylene (2-20) alkylethers and polyoxyethylene(2-20) alkylphenylethers.
 27. A composition as set forth in claim 26wherein the nonionic surfactant(s) is present in a concentration ofabout 0.5% to about 3% by weight of the composition.
 28. A liquidconcentrate herbicidal emulsion composition comprising: (i) awater-soluble herbicide in water, the water-soluble herbicide beingpresent in a concentration that is biologically effective when thecomposition is diluted in a suitable volume of water and applied to thefoliage of a susceptible plant; (ii) an oil-soluble herbicide present ina concentration that is biologically effective when the composition isdiluted in a suitable volume of water and applied to the foliage of asusceptible plant; (iii) a substantially water-immiscible organicsolvent; (iv) at least one emulsifying agent having a tertiary aminefunctionality; and (v) a stabilizing amount of one or more water-solublechlorides selected from hydrochloric acid, alkali metal chlorides,ammonium chloride, low molecular weight organic ammonium chlorides andquaternary ammonium chloride surfactants sufficient to inhibitsubstantial degradation of the oil-soluble herbicide; wherein theoil-soluble herbicide is selected from the group consisting ofacetochlor, alachlor, ametryn, amidosulfuron, anilofos, atrazine,azafenidin, azimsulfuron, benfluralin, benfuresate, bensulfuron-methyl,bensulide, benzfendizone, benzofenap, bromobutide, bromofenoxim,butachlor, butafenacil, butamifos, butralin, butylate, cafenstrole,carbetamide, chlorbromuron, chloridazon, chlorimuron-ethyl,chlorotoluron, chlorpropham, chlorsulfuron, chlorthal-dimethyl,chlorthiamid, cinidon-ethyl, cinmethylin, cinosulfuron, clomazone,clomeprop, cloransulam-methyl, cyanazine, cycloate, cyclosulfamuron,daimuron, desmedipham, desmetryn, dichlobenil, diflufenican, dimefuron,dimepiperate, dimethachlor, dimethametryn, dimethenamid, dinitramine,dinoterb, diphenamid, dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanofan, isoproturon, isouron, isoxaben,isoxaflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulfuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanil, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenylchlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.
 29. Acomposition as set forth in claim 28 wherein the emulsion comprises asuspoemulsion, a microemulsion, or a macroemulsion.
 30. A composition asset forth in claim 28 wherein the combined concentration of thewater-soluble herbicide and the oil-soluble herbicide ranges from about5% to about 50% by weight of the composition.
 31. A composition as setforth in claim 28 wherein the combined concentration of thewater-soluble herbicide and the oil-soluble herbicide ranges from about20% to about 50% by weight of the composition.
 32. A composition as setforth in claim 28 wherein the weight ratio of water-soluble herbicide tooil-soluble herbicide ranges from about 190:1 to about 1:1.
 33. Acomposition as set forth in claim 28 wherein the water-soluble herbicideis selected from the group consisting of acifluorfen, acrolein,amitrole, asulam, benazolin, bialaphos, bromacil, bromoxynil,chloramben, chloroacetic acid, clopyralid, 2,4-D, 2,4-DB, dalapon,dicamba, dichlorprop difenzoquat, diquat, endothall, fenac, fenoxaprop,flamprop, flumiclorac, fluoroglycofen, flupropanate, fomesafen,fosamine, glufosinate, glyphosate, imazameth, imazamethabenz, imazamox,imazapic, imazapyr, imazaquin, imazethapyr, ioxynil, MCPA, MCPB,mecoprop, methylarsonic acid, naptalam, nonanoic acid, paraquat,picloram, quinclorac, sulfamic acid, 2,3,6-TBA, triclopyr andwater-soluble salts thereof.
 34. A composition as set forth in claim 28wherein the water-soluble herbicide is a salt of glyphosate.
 35. Acomposition as set forth in claim 34 wherein said composition containsfrom about 50 to about 500 grams a.e. glyphosate per liter.
 36. Acomposition as set forth in claim 34 wherein said composition containsfrom about 300 to about 500 grams a.e. glyphosate per liter.
 37. Acomposition as set forth in claim 34 wherein said composition containsfrom about 360 to about 500 grams a.e. glyphosate per liter.
 38. Acomposition as set forth in claim 34 wherein the salt of glyphosate isan alkali metal, ammonium, C1-6 alkylammonium, C1-6 alkanolammonium, orC1-6 alkylsulfonium salt thereof.
 39. A composition as set forth inclaim 38 wherein the salt of glyphosate is the isopropylammonium orpotassium salt thereof.
 40. A composition as set forth in claim 28wherein the oil-soluble herbicide comprises a protoporphyrinogen oxidazeinhibitor (PPO) herbicide selected from the group consisting ofazafenidin, benzfendizone, butafenacil, cinidon-ethyl, fluazolate,flumiclorac-pentyl, flumioxazin, fluthiacet-methyl, oxadiargyl,oxadiazon, pentoxazone, profluazol, pyraflufen-ethyl, pyrazogyl,sulfentrazone and thidiazimin.
 41. A composition as set forth in claim28 wherein the organic solvent is selected such that the oil-solubleherbicide has an organic solvent/water partition coefficient, expressedas a logarithm, of about 4 or greater.
 42. A composition as set forth inclaim 41 wherein the weight ratio of organic solvent to oil-solubleherbicide ranges from about 3:1 to about 75:1.
 43. A composition as setforth in claim 41 wherein the weight ratio of organic solvent tooil-soluble herbicide ranges from about 3:1 to about 60:1.
 44. Acomposition as set forth in claim 41 wherein the weight ratio of organicsolvent to oil-soluble herbicide ranges from about 5:1 to about 50:1.45. A composition as set forth in claim 41 wherein the organic solventis an aromatic solvent.
 46. A composition as set forth in claim 41wherein the organic solvent is selected such that the oil-solubleherbicide has an organic solvent/water partition coefficient, expressedas a logarithm, of at least about 5 or greater.
 47. A composition as setforth in claim 28 wherein the water-soluble chloride stabilizing agentis present in a concentration sufficient to provide a concentration ofchloride ion of from about 0.5% to about 2.5% by weight.
 48. Acomposition as set forth in claim 47 wherein the water-soluble chloridestabilizing agent comprises ammonium chloride, sodium chloride,hydrochloric acid or a combination thereof.
 49. A composition as setforth in claim 28 wherein the total concentration of all surfactantspresent in the composition is less than about 12% by weight.
 50. Acomposition as set forth in claim 28 wherein said emulsifying agent(s)is selected from the group consisting of polyoxyethylene (2-20) tertiaryalkylamines and polyoxyethylene (2-20) tertiary alkyletheramines.
 51. Acomposition as set forth in claim 50 wherein said alkylamines andalkyletheramines have alkyl chains having from about 12 to about 18carbon atoms.
 52. A composition as set forth in claim 50 wherein saidalkylamine and/or alkyletheramine surfactant(s) comprise about 3% toabout 10% by weight of the composition.
 53. A composition as set forthin claim 28 further comprising one or more nonionic surfactants selectedfrom the group consisting of polyoxyethylene (2-20) alkylethers andpolyoxyethylene (2-20) alkylphenylethers.
 54. A composition as set forthin claim 53 wherein the nonionic surfactant(s) is present in aconcentration of about 0.5% to about 3% by weight of the composition.55. A liquid concentrate herbicidal microemulsion composition having acontinuous aqueous phase and a discontinuous oil phase, the compositioncomprising: (i) a water-soluble herbicide in said aqueous phase, thewater-soluble herbicide being present in a concentration that isbiologically effective when the composition is diluted in a suitablevolume of water and applied to the foliage of a susceptible plant; (ii)an oil-soluble herbicide in said oil phase, the oil-soluble herbicidebeing present in a concentration that is biologically effective when thecomposition is diluted in a suitable volume of water and applied to thefoliage of a susceptible plant; (iii) a stabilizing amount of one ormore water-soluble chlorides selected from hydrochloric acid, alkalimetal chlorides, ammonium chloride, low molecular weight organicammonium chlorides and quaternary ammonium chloride surfactants; and(iv) one or more surfactants present in a concentration sufficient toprovide acceptable physical stability of the emulsion and provideacceptable dispersion of the emulsion upon dilution thereof in asuitable volume of water for application to plants; wherein theoil-soluble herbicide is selected from the group consisting ofacetochlor, alachlor, ametryn, amidosulfuron, anilofos, atrazine,azafenidin, azimsulfuron, benfluralin, benfuresate, bensulfuron-methyl,bensulide, benzfendizone, benzofenap, bromobutide, bromofenoxim,butachlor, butafenacil, butamifos, butralin, butylate, cafenstrole,carbetamide, chlorbromuron, chloridazon, chlorimuron-ethyl,chlorotoluron, chlorpropham, chlorsulfuron, chlorthal-dimethyl,chlorthiamid, cinidon-ethyl, cinmethylin, cinosulfuron, clomazone,clomeprop, cloransulam-methyl, cyanazine, cycloate, cyclosulfamuron,daimuron, desmedipham, desmetryn, dichlobenil, diflufenican, dimefuron,dimepiperate, dimethachlor, dimethametryn, dimethenamid, dinitramine,dinoterb, diphenamid, dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanofan, isoproturon, isouron, isoxaben,isoxaflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulfuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanil, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenylchlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.
 56. Acomposition as set forth in claim 55 wherein the combined concentrationof the water-soluble herbicide and the oil-soluble herbicide ranges fromabout 5% to about 50% by weight of the composition.
 57. A composition asset forth in claim 55 wherein the combined concentration of thewater-soluble herbicide and the oil-soluble herbicide ranges from about20% to about 50% by weight of the composition.
 58. A composition as setforth in claim 55 wherein the weight ratio of water-soluble herbicide tooil-soluble herbicide ranges from about 190:1 to about 1:1.
 59. Acomposition as set forth in claim 55 wherein the water-soluble herbicideis selected from the group consisting of acifluorfen, acrolein,amitrole, asulam, benazolin, bialaphos, bromacil, bromoxynil,chloramben, chloroacetic acid, clopyralid, 2,4-D, 2,4-DB, dalapon,dicamba, dichlorprop difenzoquat, diquat, endothall, fenac, fenoxaprop,flamprop, flumiclorac, fluoroglycofen, flupropanate, fomesafen,fosamine, glufosinate, glyphosate, imazameth, imazamethabenz, imazamox,imazapic, imazapyr, imazaquin, imazethapyr, ioxynil, MCPA, MCPB,mecoprop, methylarsonic acid, naptalam, nonanoic acid, paraquat,picloram, quinclorac, sulfamic acid, 2,3,6-TBA, triclopyr andwater-soluble salts thereof.
 60. A composition as set forth in claim 55wherein the water-soluble herbicide is a salt of glyphosate.
 61. Acomposition as set forth in claim 60 wherein said composition containsfrom about 50 to about 500 grams a.e. glyphosate per liter.
 62. Acomposition as set forth in claim 60 wherein said composition containsfrom about 300 to about 500 grams a.e. glyphosate per liter.
 63. Acomposition as set forth in claim 60 wherein said composition containsfrom about 360 to about 500 grams a.e. glyphosate per liter.
 64. Acomposition as set forth in claim 60 wherein the salt of glyphosate isan alkali metal, ammonium, C1-6 alkylammonium, C1-6 alkanolammonium, orC1-6 alkylsulfonium salt thereof.
 65. A composition as set forth inclaim 64 wherein the salt of glyphosate is the isopropylammonium orpotassium salt thereof.
 66. A composition as set forth in claim 55wherein the oil-soluble herbicide comprises a protoporphyrinogen oxidazeinhibitor (PPO) herbicide selected from the group consisting ofazafenidin, benzfendizone, butafenacil, cinidon-ethyl, fluazolate,flumiclorac-pentyl, flumioxazin, fluthiacet-methyl, oxadiargyl,oxadiazon, pentoxazone, profluazol, pyraflufen-ethyl, pyrazogyl,sulfentrazone and thidiazimin.
 67. A composition as set forth in claim55 further comprising a substantially water-immiscible organic solventin said oil phase, wherein the organic solvent is selected such that theoil-soluble herbicide has an organic solvent/water partitioncoefficient, expressed as a logarithm, of about 4 or greater.
 68. Acomposition as set forth in claim 67 wherein the weight ratio of organicsolvent to oil-soluble herbicide ranges from about 3:1 to about 75:1.69. A composition as set forth in claim 67 wherein the weight ratio oforganic solvent to oil-soluble herbicide ranges from about 3:1 to about60:1.
 70. A composition as set forth in claim 67 wherein the weightratio of organic solvent to oil-soluble herbicide ranges from about 5:1to about 50:1.
 71. A composition as set forth in claim 67 wherein theorganic solvent is an aromatic solvent.
 72. A composition as set forthin claim 67 wherein the organic solvent is selected such that theoil-soluble herbicide has an organic solvent/water partitioncoefficient, expressed as a logarithm, of at least about 5 or greater.73. A composition as set forth in claim 55 wherein said water-solublechloride stabilizing agent is present in a concentration sufficient toprovide a concentration of chloride ion of from about 0.5% to about 2.5%by weight.
 74. A composition as set forth in claim 55 wherein saidwater-soluble chloride stabilizing agent comprises ammonium chloride,sodium chloride, hydrochloric acid or a combination thereof.
 75. Acomposition as set forth in claim 55 wherein the total concentration ofall surfactants present in the composition is less than about 12% byweight.
 76. A composition as set forth in claim 55 further comprisingone or more surfactants selected from the group consisting ofpolyoxyethylene (2-20) tertiary alkylamines and polyoxyethylene (2-20)tertiary alkyletheramines.
 77. A composition as set forth in claim 76wherein said alkylamines and alkyletheramines have alkyl chains havingfrom about 12 to about 18 carbon atoms.
 78. A composition as set forthin claim 76 wherein said alkylamine and/or alkyletheramine surfactant(s)comprise about 3% to about 10% by weight of the composition.
 79. Acomposition as set forth in claim 55 further comprising one or morenonionic surfactants selected from the group consisting ofpolyoxyethylene (2-20) alkylethers and polyoxyethylene (2-20)alkylphenylethers.
 80. A composition as set forth in claim 79 whereinthe nonionic surfactant(s) is present in a concentration of about 0.5%to about 3% by weight of the composition.
 81. A composition as set forthin claim 55 wherein the aqueous phase has a pH in a range that isminimally conducive to chemical degradation of the water-solubleherbicide.
 82. A liquid concentrate herbicidal microemulsion compositionhaving a continuous aqueous phase and a discontinuous oil phase, thecomposition comprising: (i) a water-soluble herbicide in said aqueousphase, the water-soluble herbicide being present in a concentration thatis biologically effective when the composition is diluted in a suitablevolume of water and applied to the foliage of a susceptible plant; (ii)an oil-soluble herbicide in said oil phase, the oil-soluble herbicidebeing present in a concentration that is biologically effective when thecomposition is diluted in a suitable volume of water and applied to thefoliage of a susceptible plant; (iii) a substantially water-immiscibleorganic solvent in said oil phase, wherein the organic solvent isselected such that the oil-soluble herbicide has an organicsolvent/water partition coefficient, expressed as a logarithm, of about4 or greater; (iv) at least one emulsifying agent having a tertiaryamine functionality, the emulsifying agent being present in aconcentration sufficient to provide acceptable physical stability of themicroemulsion; (v) a stabilizing agent present in a concentrationsufficient to inhibit substantial degradation of the oil-solubleherbicide; and (vi) one or more dispersing agents present in aconcentration sufficient to provide acceptable dispersion of themicroemulsion upon dilution thereof in a suitable volume of water forapplication to plants, but not sufficient to destabilize themicroemulsion prior to such dilution; wherein the oil-soluble herbicideis selected from the group consisting of acetochlor, alachlor, ametryn,amidosulfuron, anilofos, atrazine, azafenidin, azimsulfuron,benfluralin, benfuresate, bensulfuron-methyl, bensulide, benzfendizone,benzofenap, bromobutide, bromofenoxim, butachlor, butafenacil,butamifos, butralin, butylate, cafenstrole, carbetamide, chlorbromuron,chloridazon, chlorimuron-ethyl, chlorotoluron, chlorpropham,chlorsulfuron, chlorthal-dimethyl, chlorthiamid, cinidon-ethyl,cinmethylin, cinosulfuron, clomazone, clomeprop, cloransulam-methyl,cyanazine, cycloate, cyclosulfamuron, daimuron, desmedipham, desmetryn,dichlobenil, diflufenican, dimefuron, dimepiperate, dimethachlor,dimethametryn, dimethenamid, dinitramine, dinoterb, diphenamid,dithiopyr, diuron, EPTC, esprocarb, ethalfluralin,ethametsulfuron-methyl, ethofumesate, ethoxysulfuron, etobenzanid,fenoxaprop-ethyl, fenuron, flamprop-methyl, flazasulfuron, fluazolate,fluchloralin, flumetsulam, flumiclorac-pentyl, flumioxazin, fluometuron,fluorochloridone, flupoxam, flurenol, fluridone,fluroxypyr-1-methylheptyl, flurtamone, fluthiacet-methyl, halosulfuron,hexazinone, imazosulfuron, indanofan, isoproturon, isouron, isoxaben,isoxaflutole, lenacil, linuron, mefenacet, metamitron, metazachlor,methabenzthiazuron, methyldymron, metobenzuron, metobromuron,metolachlor, metosulam, metoxuron, metribuzin, metsulfuron, molinate,monolinuron, naproanilide, napropamide, neburon, nicosulfuron,norflurazon, orbencarb, oryzalin, oxadiargyl, oxadiazon, oxasulfuron,pebulate, pendimethalin, pentanochlor, pentoxazone, phenmedipham,piperophos, pretilachlor, primisulfuron, prodiamine, profluazol,prometon, prometryn, propachlor, propanil, propazine, propham,propisochlor, propyzamide, prosulfocarb, prosulfuron, pyraflufen-ethyl,pyrazogyl, pyrazolynate, pyrazosulfuron-ethyl, pyrazoxyfen,pyributicarb, pyridate, pyriminobac-methyl, quinclorac, quinmerac,rimsulfuron, siduron, simazine, simetryn, sulcotrione, sulfentrazone,sulfometuron, sulfosulfuron, tebutam, tebuthiuron, terbacil, terbumeton,terbuthylazine, terbutryn, thenylchlor, thiazopyr, thidiazimin,thifensulfuron, thiobencarb, tiocarbazil, triallate, triasulfuron,tribenuron, trietazine, trifluralin, triflusulfuron and vernolate.
 83. Acomposition as set forth in claim 82 wherein the combined concentrationof the water-soluble herbicide and the oil-soluble herbicide ranges fromabout 5% to about 50% by weight of the composition.
 84. A composition asset forth in claim 82 wherein the combined concentration of thewater-soluble herbicide and the oil-soluble herbicide ranges from about20% to about 50% by weight of the composition.
 85. A composition as setforth in claim 82 wherein the weight ratio of water-soluble herbicide tooil-soluble herbicide ranges from about 160:1 to about 1:1.
 86. Acomposition as set forth in claim 82 wherein the water-soluble herbicideis selected from the group consisting of acifluorfen, acrolein,amitrole, asulam, benazolin, bialaphos, bromacil, bromoxynil,chloramben, chloroacetic acid, clopyralid, 2,4-D, 2,4-DB, dalapon,dicamba, dichlorprop difenzoquat, diquat, endothall, fenac, fenoxaprop,flamprop, flumiclorac, fluoroglycofen, flupropanate, fomesafen,fosamine, glufosinate, glyphosate, imazameth, imazamethabenz, imazamox,imazapic, imazapyr, imazaquin, imazethapyr, ioxynil, MCPA, MCPB,mecoprop, methylarsonic acid, naptalam, nonanoic acid, paraquat,picloram, quinclorac, sulfamic acid, 2,3,6-TBA, triclopyr andwater-soluble salts thereof.
 87. A composition as set forth in claim 82wherein the water-soluble herbicide is a salt of glyphosate.
 88. Acomposition as set forth in claim 87 wherein said composition containsfrom about 50 to about 500 grams a.e. glyphosate per liter.
 89. Acomposition as set forth in claim 87 wherein said composition containsfrom about 300 to about 500 grams a.e. glyphosate per liter.
 90. Acomposition as set forth in claim 87 wherein said composition containsfrom about 360 to about 500 grams a.e. glyphosate per liter.
 91. Acomposition as set forth in claim 87 wherein the salt of glyphosate isan alkali metal, ammonium, C1-6 alkylammonium, C1-6 alkanolammonium, orC1-6 alkylsulfonium salt thereof.
 92. A composition as set forth inclaim 91 wherein the salt of glyphosate is the isopropylammonium orpotassium salt thereof.
 93. A composition as set forth in claim 82wherein the oil-soluble herbicide comprises a protoporphyrinogen oxidazeinhibitor (PPO) herbicide selected from the group consisting ofazafenidin, benzfendizone, butafenacil, cinidon-ethyl, fluazolate,flumiclorac-pentyl, flumioxazin, fluthiacet-methyl, oxadiargyl,oxadiazon, pentoxazone, profluazol, pyraflufen-ethyl, pyrazogyl,sulfentrazone and thidiazimin.
 94. A composition as set forth in claim82 wherein the weight ratio of organic solvent to oil-soluble herbicideranges from about 3:1 to about 75:1.
 95. A composition as set forth inclaim 82 wherein the weight ratio of organic solvent to oil-solubleherbicide ranges from about 3:1 to about 60:1.
 96. A composition as setforth in claim 82 wherein the weight ratio of organic solvent tooil-soluble herbicide ranges from about 5:1 to about 50:1.
 97. Acomposition as set forth in claim 82 wherein the organic solvent is anaromatic solvent.
 98. A composition as set forth in claim 82 wherein theorganic solvent is selected such that the oil-soluble herbicide has anorganic solvent/water partition coefficient, expressed as a logarithm,of at least about 5 or greater.
 99. A composition as set forth in claim82 wherein the stabilizing agent comprises one or more water-solublechlorides selected from hydrochloric acid, alkali metal chlorides,ammonium chloride, low molecular weight organic ammonium chlorides andquaternary ammonium chloride surfactants.
 100. A composition as setforth in claim 99 wherein the stabilizing agent is present in aconcentration sufficient to provide a concentration of chloride ion offrom about 0.5% to about 2.5% by weight.
 101. A composition as set forthin claim 99 wherein the stabilizing agent comprises ammonium chloride,sodium chloride, hydrochloric acid or a combination thereof.
 102. Acomposition as set forth in claim 82 wherein the total concentration ofall surfactants present in the composition is less than about 12% byweight.
 103. A composition as set forth in claim 82 wherein theemulsifying agent(s) comprises one or more surfactants selected from thegroup consisting of polyoxyethylene (2-20) tertiary alkylamines andpolyoxyethylene (2-20) tertiary alkyletheramines.
 104. A composition asset forth in claim 103 wherein said alkylamines and alkyletheramineshave alkyl chains having from about 12 to about 18 carbon atoms.
 105. Acomposition as set forth in claim 103 wherein said alkylamine and/oralkyletheramine surfactant(s) comprise about 3% to about 10% by weightof the composition.
 106. A composition as set forth in claim 82 whereinsaid dispersing agent(s) comprise one or more nonionic surfactantsselected from the group consisting of polyoxyethylene (2-20) alkylethersand polyoxyethylene (2-20) alkylphenylethers.
 107. A composition as setforth in claim 106 wherein the nonionic surfactant(s) is present in aconcentration of about 0.5% to about 3% by weight of the composition.108. A composition as set forth in claim 82 wherein the aqueous phasehas a pH in a range that is minimally conducive to chemical degradationof the water-soluble herbicide.
 109. A liquid concentrate herbicidalmicroemulsion composition comprising: (i) a continuous aqueous phasecomprising N-(phosphonomethyl)glycine or a salt thereof, theN-(phosphonomethyl)glycine being present in a concentration that isbiologically effective when the composition is diluted in a suitablevolume of water and applied to the foliage of a susceptible plant; (ii)a discontinuous oil phase comprising an oil-soluble protoporphyrinogenoxidase inhibitor (PPO) herbicide, the PPO herbicide being present in aconcentration that is biologically effective when the composition isdiluted in a suitable volume of water and applied to the foliage of asusceptible plant; (iii) a substantially water-immiscible organicsolvent in said oil phase, wherein the organic solvent is selected suchthat the oil-soluble herbicide has an organic solvent/water partitioncoefficient, expressed as a logarithm, of about 4 or greater; (iv) atleast one emulsifying agent having a tertiary amine functionality, theemulsifying agent being present in a concentration sufficient to provideacceptable physical stability of the microemulsion; (v) a stabilizingagent present in a concentration sufficient to inhibit substantialdegradation of the PPO herbicide; and (vi) one or more dispersing agentspresent in a concentration sufficient to provide acceptable dispersionof the microemulsion upon dilution thereof in a suitable volume of waterfor application to plants, but not sufficient to destabilize themicroemulsion prior to such dilution; wherein the PPO herbicide isselected from the group consisting of azafenidin, benzfendizone,butafenacil, cinidon-ethyl, fluazolate, flumiclorac-pentyl, flumioxazin,fluthiacet-methyl, oxadiargyl, oxadiazon, pentoxazone, profluazol,pyraflufen-ethyl, pyrazogyl, sulfentrazone and thidiazimin.
 110. Acomposition as set forth in claim 109 wherein the combined concentrationof N-(phosphonomethyl)glycine and the PPO herbicide ranges from about 5%to about 50% by weight of the composition.
 111. A composition as setforth in claim 109 wherein the combined concentration ofN-(phosphonomethyl)glycine and the PPO herbicide ranges from about 20%to about 50% by weight of the composition.
 112. A composition as setforth in claim 109 wherein the weight ratio ofN-(phosphonomethyl)glycine to PPO herbicide ranges from about 160:1 toabout 1:1.
 113. A composition as set forth in claim 109 wherein saidN-(phosphonomethyl)glycine is an alkali metal, ammonium, C1-6alkylammonium, C1-6 alkanolammonium, or C1-6 alkylsulfonium saltthereof.
 114. A composition as set forth in claim 113 wherein the saltof N-(phosphonomethyl)glycine is the isopropylammonium or potassium saltthereof.
 115. A composition as set forth in claim 109 wherein saidcomposition contains from about 50 to about 500 grams a.e.N-(phosphonomethyl)glycine per liter.
 116. A composition as set forth inclaim 109 wherein said composition contains from about 300 to about 500grams a.e. N-(phosphonomethyl)glycine per liter.
 117. A composition asset forth in claim 109 wherein said composition contains from about 360to about 500 grams a.e. N-(phosphonomethyl)glycine per liter.
 118. Acomposition as set forth in claim 109 wherein the weight ratio oforganic solvent to PPO herbicide ranges from about 3:1 to about 75:1.119. A composition as set forth in claim 109 wherein the weight ratio oforganic solvent to PPO herbicide ranges from about 3:1 to about 60:1.120. A composition as set forth in claim 109 wherein the weight ratio oforganic solvent to PPO herbicide ranges from about 5:1 to about 50:1.121. A composition as set forth in claim 109 wherein the organic solventis an aromatic solvent.
 122. A composition as set forth in claim 109wherein the organic solvent is selected such that the PPO herbicide hasan organic solvent/water partition coefficient, expressed as alogarithm, of at least about 5 or greater.
 123. A composition as setforth in claim 109 wherein the stabilizing agent comprises one or morewater-soluble chlorides selected from hydrochloric acid, alkali metalchlorides, ammonium chloride, low molecular weight organic ammoniumchlorides and quaternary ammonium chloride surfactants.
 124. Acomposition as set forth in claim 123 wherein the stabilizing agent ispresent in a concentration sufficient to provide a concentration ofchloride ion of from about 0.5% to about 2.5% by weight.
 125. Acomposition as set forth in claim 124 wherein the stabilizing agentcomprises ammonium chloride, sodium chloride, hydrochloric acid or acombination thereof.
 126. A composition as set forth in claim 109wherein the total concentration of all surfactants present in thecomposition is less than about 12% by weight.
 127. A composition as setforth in claim 109 wherein the emulsifying agent(s) comprises one ormore surfactants selected from the group consisting of polyoxyethylene(2-20) tertiary alkylamines and polyoxyethylene (2-20) tertiaryalkyletheramines.
 128. A composition as set forth in claim 127 whereinsaid alkylamines and alkyletheramines have alkyl chains having fromabout 12 to about 18 carbon atoms.
 129. A composition as set forth inclaim 127 wherein said alkylamine and/or alkyletheramine surfactant(s)comprise about 3% to about 10% by weight of the composition.
 130. Acomposition as set forth in claim 109 wherein said dispersing agent(s)comprise one or more nonionic surfactants selected from the groupconsisting of polyoxyethylene (2-20) alkylethers and polyoxyethylene(2-20) alkylphenylethers.
 131. A composition as set forth in claim 130wherein the nonionic surfactant(s) is present in a concentration ofabout 0.5% to about 3% by weight of the composition.
 132. A compositionas set forth in claim 109 wherein the aqueous phase has a pH in a rangethat is minimally conducive to chemical degradation ofN-(phosphonomethyl)glycine.
 133. A process for controlling the growth ofor killing unwanted plants, the process comprising: diluting a liquidconcentrate herbicidal composition of claim 1 in a suitable volume ofwater to form a plant treatment composition; and, applying said planttreatment composition to the foliage of said unwanted plants.
 134. Aprocess as set forth in claim 133 wherein the water-soluble herbicidepresent in the composition is a salt of N-(phosphonomethyl)glycine.